[Federal Register Volume 69, Number 145 (Thursday, July 29, 2004)]
[Proposed Rules]
[Pages 45506-45534]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-16576]



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Part V





Department of Energy





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Office of Energy Efficiency and Renewable Energy



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10 CFR Part 432



Energy Conservation Program: Test Procedures for Distribution 
Transformers; Proposed Rule

  Federal Register / Vol. 69, No. 145 / Thursday, July 29, 2004 / 
Proposed Rules  

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DEPARTMENT OF ENERGY

Office of Energy Efficiency and Renewable Energy

10 CFR Part 432

[Docket No. EE-TP-98-550]
RIN 1904-AA85


Energy Conservation Program: Test Procedures for Distribution 
Transformers

AGENCY: Office of Energy Efficiency and Renewable Energy, Department of 
Energy.

ACTION: Supplemental notice of proposed rulemaking and public meeting.

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SUMMARY: The Department of Energy (DOE or the Department) previously 
published a notice of proposed rulemaking to adopt test procedures for 
measuring the energy efficiency of distribution transformers under the 
Energy Policy and Conservation Act (EPCA or the Act), definitions to 
delineate the products covered by the test procedures and provisions 
(including a sampling plan) for implementing the test procedures. The 
Department now proposes to adopt revised test procedures for 
distribution transformers, primarily based upon existing industry 
standards. The proposed rule also contains revised definitions and 
provisions to implement the test procedures, calculation methods that 
manufacturers could use to determine the efficiency of some of their 
models, and enforcement methods for distribution transformers. The 
Department would use the test procedures in evaluating whether, and to 
what extent, energy conservation standards are warranted for 
distribution transformers. If standards are promulgated, then these 
test procedures and the other provisions proposed today would be used 
to determine efficiency and assess compliance of the transformers 
subject to the standards.

DATES: The Department will hold a public meeting on the matters 
addressed in this document, on Monday, September 27, 2004, beginning at 
9 a.m. in Room 1E-245, in Washington, DC. The Department must receive 
requests to speak at the meeting, and a signed original and electronic 
copy of statements to be given at the meeting, no later than 4 p.m., 
Monday, September 13, 2004. The Department will accept written 
comments, data, and information in response to this notice before or 
after the public meeting, but no later than Monday, November 8, 2004. 
See section IV, ``Public Participation,'' of this notice for details.

ADDRESSES: You may submit comments, identified by docket number EE-TP-
98-550 and/or RIN number 1904-AA85, by any of the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the instructions for submitting comments.
     E-mail: [email protected]. Include EE-
TP-98-550 and/or RIN 1904-AA85 in the subject line of the message.
     Mail: Ms. Brenda Edwards-Jones, U.S. Department of Energy, 
Building Technologies Program, Mailstop EE-2J, SNOPR for Distribution 
Transformer Test Procedures, EE-TP-98-550 and/or RIN 1904-AA85, 1000 
Independence Avenue, SW., Washington, DC, 20585-0121. Telephone: (202) 
586-2945. Please submit one signed original paper copy.
     Hand Delivery/Courier: Ms. Brenda Edwards-Jones, U.S. 
Department of Energy, Building Technologies Program, Room 1J-018, 1000 
Independence Avenue, SW., Washington, DC, 20585.
    Instructions: All submissions received must include the agency name 
and docket number or Regulatory Information Number (RIN) for this 
rulemaking. For detailed instructions on submitting comments and 
additional information on the rulemaking process, see section IV of 
this document (Public Participation).
    Docket: For access to the docket to read background documents or 
comments received, go to the U.S. Department of Energy, Forrestal 
Building, Room 1J-018 (Resource Room of the Building Technologies 
Program), 1000 Independence Avenue, SW., Washington, DC, (202) 586-
9127, between 9 a.m. and 4 p.m., Monday through Friday, except Federal 
holidays. Please call Ms. Brenda Edwards-Jones at the above telephone 
number for additional information regarding visiting the Resource Room. 
Please note: The Department's Freedom of Information Reading Room 
(formerly Room 1E-190 at the Forrestal Building) is no longer housing 
rulemaking materials.

FOR FURTHER INFORMATION CONTACT: Cyrus Nasseri, Project Manager, Test 
Procedures for Distribution Transformers, Docket No. EE-TP-98-550, U.S. 
Department of Energy, Energy Efficiency and Renewable Energy, Building 
Technologies Program, EE-2J, 1000 Independence Avenue, SW., Washington, 
DC 20585-0121, (202) 586-9138, E-mail: [email protected].
    Francine Pinto, Esq., or Thomas B. DePriest, Esq., U.S. Department 
of Energy, Office of General Counsel, GC-72, 1000 Independence Avenue, 
SW., Washington, DC 20585-0121, (202) 586-9507, E-mail: 
[email protected], or [email protected].

SUPPLEMENTARY INFORMATION:

I. Introduction
    A. Authority and Background
    B. Summary of the Proposed Rule
II. Discussion
    A. The Test Procedure for Distribution Transformers
    1. General Discussion
    2. Reference Conditions
    B. Transformers Subject to the Test Procedure
    1. Background
    2. Changes to, and retention of, provisions in the 1998 proposed 
rule
    3. Exclusions discussed in the 1999 reopening notice
    4. Additional exclusions drawn from NEMA TP 1
    5. Definitions of excluded transformers
    C. Basic Model
    D. Manufacturer's Determination of Efficiency
    E. Enforcement Procedures
    F. New Part 432
III. Procedural Requirements
    A. Review Under Executive Order 12866
    B. Review Under the Regulatory Flexibility Act
    C. Review Under the Paperwork Reduction Act
    D. Review Under the National Environmental Policy Act
    E. Review Under Executive Order 13132
    F. Review Under Executive Order 12988
    G. Review Under the Unfunded Mandates Reform Act of 1995
    H. Review Under the Treasury and General Government 
Appropriations Act, 1999
    I. Review Under Executive Order 12630
    J. Review Under the Treasury and General Government 
Appropriations Act, 2001
    K. Review Under Executive Order 13211
    L. Review Under Section 32 of the Federal Energy Administration 
Act of 1974
IV. Public Participation
    A. Attendance at Public Meeting
    B. Procedure for Submitting Requests to Speak
    C. Conduct of Public Meeting
    D. Submission of Comments

I. Introduction

A. Authority and Background

    Part C of Title III of the Energy Policy and Conservation Act 
(EPCA) provides for an energy conservation program for certain 
industrial equipment. (42 U.S.C. 6311-6317) Section 346 of EPCA states 
that the Secretary of Energy (Secretary) must prescribe testing 
requirements and energy conservation standards for those ``distribution 
transformers'' for which the Secretary determines that standards 
``would be technologically feasible and economically justified, and 
would result in significant energy savings.'' (42 U.S.C. 6317(a)) On 
October 22, 1997, the

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Department issued a notice setting forth its determination (hereafter 
referred to as the ``Determination'') that, based on the best 
information currently available, energy conservation standards for 
electric distribution transformers appear to be technologically 
feasible and economically justified, and are likely to result in 
significant energy savings. 62 FR 54809. The Determination was based, 
in part, on analyses conducted by the Oak Ridge National Laboratory 
(ORNL), as explained in reports issued in July 1996 and September 
1997.\1\ 62 FR at 54811-54816.
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    \1\ The titles and references for these reports are 
``Determination Analysis of Energy Conservation Standards for 
Distribution Transformers, ORNL-6847'' and ``Supplement to the 
`Determination Analysis' (ORNL-6847) and Analysis of NEMA Efficiency 
Standard for Distribution Transformers, ORNL-6925.''
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    The Department subsequently began the process for its adoption of 
test procedures for distribution transformers. On February 10, 1998, 
the Department held a public workshop (1998 workshop) to discuss the 
following issues: (a) Adoption of national and international consensus 
standards as the test procedures for determining the energy efficiency 
of distribution transformers, (b) defining the transformers that the 
test procedures will cover, (c) imposition of a burden on industry, 
especially on manufacturers, with additional testing and data 
processing, (d) definition of ``basic model'' for distribution 
transformers, (e) sampling plan for units to be tested, (f) selection 
of an energy consumption measure for distribution transformers, (g) 
selection of reference temperatures, (h) requirements for applying 
corrections to measurement data, and (i) requirements for quality 
assurance in testing. The Department also gave interested parties an 
opportunity to submit comments on these issues.
    In 1998, the National Electrical Manufacturers Association (NEMA) 
published ``NEMA Standards Publication No. TP 2-1998, Standard Test 
Method for Measuring the Energy Consumption of Distribution 
Transformers,'' (NEMA TP 2) a publication that extracts and presents 
the pertinent parts of the current industry standards for distribution 
transformer efficiency testing. NEMA TP 2 presents a weighted average 
method to use to compute the energy efficiency of transformers, in 
order to demonstrate compliance with the efficiency levels in NEMA 
Standard TP 1-1996 (NEMA TP 1).\2\ Comments received at the 1998 
workshop, written comments associated with this workshop, and NEMA TP 2 
formed the basis for preparing the November 12, 1998, Notice of 
Proposed Rulemaking (the ``1998 proposed rule''). 63 FR 63359.
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    \2\ NEMA TP 1 contains suggested efficiency levels. Its full 
name and title are ``NEMA Standards Publication No. TP 1-1996, Guide 
for Determining Energy Efficiency for Distribution Transformers.''
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    In the 1998 proposed rule, the Department proposed to adopt test 
procedures that (1) it would use to evaluate distribution transformers 
for efficiency standards, and (2) manufacturers and DOE would use to 
determine the efficiency of any transformers which the standards 
covered. DOE proposed to incorporate by reference as its test 
procedures, provisions from either Institute of Electrical and 
Electronics Engineers (IEEE) Standards C57.12.90-1993 and C57.12.91-
1993 (using IEEE C57.12.00-1993 as an additional reference source), or 
NEMA TP 2. The 1998 proposed rule also included proposed definitions of 
``distribution transformer'' and related terms, of terms used in the 
test procedure provisions, and of ``basic model,'' and proposed a 
sampling plan for applying the test procedures to perform compliance 
testing. The sampling approach was based on the plan for compliance 
testing in 10 CFR part 430, which contains energy efficiency 
requirements for consumer products, but with modifications geared to 
transformers and a minimum sample size of five units. The Department 
selected this approach because it appeared to provide a satisfactory 
balance between assuring accuracy of efficiency ratings for 
distribution transformers and minimizing the test burden on 
manufacturers. The Department also sought comment on three alternative 
compliance approaches for basic models produced in small numbers.
    DOE held a public hearing on January 6, 1999, on the 1998 proposed 
rule and received nine written comments. After reviewing the oral and 
written comments, DOE concluded that the comments raised a number of 
significant issues that required additional analysis. On June 23 1999, 
the Department reopened the comment period on the 1998 proposed rule, 
64 FR 3343, (the ``1999 reopening notice'') to provide an opportunity 
for additional public comment on the following issues: (a) The 
suitability of NEMA TP 2 for adoption as the DOE test procedure; (b) 
the adequacy of stakeholder opportunity to review NEMA TP 2; (c) the 
transformers covered under the definition of ``distribution 
transformer;'' (d) the suitability of the definition of ``basic model'' 
for the purpose of grouping transformers to limit the test burden; and 
(e) the appropriateness of the proposed sampling plan and a number of 
alternatives for demonstrating compliance. The Department received five 
comments in response to the 1999 reopening notice and two additional 
comments during the development of today's proposed test procedure. 
These comments are addressed throughout section II of this supplemental 
notice of proposed rulemaking.
    Finally, concurrent with this rulemaking, the Department has 
evaluated the establishment of energy conservation standards for 
distribution transformers. On October 2, 2000, the Department made 
available a Framework Document for Distribution Transformer Energy 
Conservation Standards Rulemaking, which was the subject of a public 
workshop on November 1, 2000, and on which stakeholders submitted 
written comments before and after the workshop. 65 FR 59761 (October 6, 
2000). Thereafter, the Department visited manufacturers of distribution 
transformers and posted on DOE's Web site \3\ several draft reports 
concerning the development of standards for these transformers. The 
next step in this process is the Department's issuance of an Advance 
Notice of Proposed Rulemaking (ANOPR) for distribution transformer 
standards. The Department expects to publish the ANOPR in the Federal 
Register later this year.
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    \3\ http://www.eere.energy.gov/buildings/appliance_standards/commercial/dist_transformers.html.
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B. Summary of the Proposed Rule

    In today's notice, the Department proposes to adopt a new test 
procedure for determining the energy efficiency of distribution 
transformers. The test procedure consists primarily of test methods 
contained in IEEE Standards C57.12.90-1999 and C57.12.91-2001, and NEMA 
TP 2. Initially, the Department would use the test procedure to test 
distribution transformers for which it is considering energy 
conservation standards. If DOE promulgates minimum efficiency 
standards, the Department would then require manufacturers to use the 
test procedure to determine compliance with the standards and as a 
basis for efficiency representations for transformers they produce that 
the standards cover. The Department would also use the test procedure 
in enforcement proceedings concerning compliance with standards or 
labeling requirements.
    The proposed test procedure is a ``stand alone'' document. Thus, 
the

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language of today's proposed rule sets forth all testing requirements, 
without reference to other sources, for determining the energy 
efficiency of distribution transformers. The measurement of electric 
power consumed by the transformer is in the form of no-load and load 
losses. The proposed rule specifies methods with which to measure the 
following quantities: Temperature of the windings and the core, 
current, voltage, waveform, and direct current resistance of the 
windings. The proposed rule also contains definitions that establish 
which transformers the test procedure covers and that clarify terms 
used in the test procedure. In addition, to reduce the number of 
transformers that manufacturers would have to test, the Department 
proposes to define ``basic model,'' proposes a sampling plan, and 
proposes to allow manufacturers to use alternative methods, other than 
testing, for determining the efficiency of some basic models. Finally, 
the proposed rule also sets forth enforcement procedures, including a 
testing protocol, for distribution transformers.
    The Department's adoption of uniform test procedures would not 
necessarily mean that it would adopt a single efficiency standard or 
set of labeling requirements for all transformers that today's proposed 
rule covers. In the separate rulemaking proceeding concerning energy 
conservation standards for distribution transformers, the Department 
intends to divide such transformers into classes and may conclude that 
standards are not warranted for some classes of transformers that are 
within the scope of today's test procedure. Furthermore, for the 
classes for which DOE decides to adopt standards, it may create a 
separate standard for each class of products where the record indicates 
the products include a utility or performance-related feature that 
other products lack and that affects energy efficiency.

II. Discussion

A. The Test Procedure for Distribution Transformers

1. General Discussion
    The Department developed today's proposed test procedure in order 
to have a single primary reference standard that would clearly set 
forth all testing requirements for the distribution transformers that 
might be covered by an EPCA energy conservation standard. DOE adapted 
virtually all of the provisions of the test procedure from NEMA TP 2 
and the following four widely used IEEE standards: (1) IEEE C57.12.90-
1999, ``IEEE Standard Test Code for Liquid-Immersed Distribution, Power 
and Regulating Transformers and IEEE Guide for Short Circuit Testing of 
Distribution and Power Transformers,'' (2) IEEE C57.12.91-2001, ``IEEE 
Standard Test Code for Dry-Type Distribution and Power Transformers,'' 
(3) IEEE C57.12.00-2000, ``IEEE Standard General Requirements for 
Liquid-Immersed Distribution, Power and Regulating Transformers,'' and 
(4) IEEE C57.12.01-1998, ``IEEE Standard General Requirements for Dry-
Type Distribution and Power Transformers Including those with Solid 
Cast and/or Resin Encapsulated Windings.'' \4\
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    \4\ This discussion does not address section 7 of NEMA TP 2, 
``Demonstration of Compliance,'' which is discussed in section II-D.
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    IEEE C57.12.90-1999 and IEEE C57.12.91-2001 address tests and 
measurements leading to the energy consumption and efficiency values. 
IEEE C57.12.00-2000 and C57.12.01-1998 complement IEEE C57.12.90-1999 
and IEEE C57.12.91-2001 by specifying requirements such as measurement 
tolerances, which are critical for defining the testing conditions. 
Each of these four IEEE standards contains different elements of the 
energy efficiency test procedure for distribution transformers, as well 
as material not required for efficiency testing. Thus, if the 
Department were to prescribe the transformer test procedure by 
reference to these sources, it would require the user to consult 
several references, and applicable sections and clauses within those 
references, in order to construct a single test procedure. DOE believes 
that having a single, reference test procedure document would enhance 
the convenience to users and reduce the potential for misinterpretation 
of testing requirements.
    Because NEMA TP 2 was designed to be a document that would contain 
all applicable testing provisions, the Department considered adopting 
it as the DOE test procedure. 63 FR at 63362, 63370-72; 64 FR at 33431-
32. The Department therefore reviewed NEMA TP 2 and compared it with 
the similar material in the IEEE standards. NEMA TP 2 excerpts the 
information pertinent to transformer efficiency testing from these 
standards (using earlier editions of the standards), and presents it in 
abbreviated form. As a result of its review, the Department determined 
that NEMA TP 2 lacks the clarity and detail required in a regulatory 
document, and also contains a number of technical and typographical 
errors. Consequently, DOE is not proposing to use it as the DOE test 
procedure. Nevertheless, because NEMA TP 2 brings transformer 
efficiency testing provisions into a single document, the Department 
used it to develop today's proposed test procedure, which is designed 
to approach the level of detail of the IEEE standards. The following 
are examples of the ways in which the Department found NEMA TP 2 to be 
unsatisfactory for use as the DOE test procedure, and in which today's 
proposed test procedure differs from NEMA TP 2:
    (1) Section 3 in NEMA TP 2, Resistance Measurements, contains 
insufficient detail, particularly in describing instrumentation. The 
proposed test procedure provides greater detail on the description of 
instrumentation, especially resistance bridges and their operating 
equations, and provides more information on temperature measurements.
    (2) Figures 2 and 3 in NEMA TP 2 are too crowded with information. 
As a result, the graphics and print symbols are too small, some to the 
point of being unreadable. The proposed test procedure seeks to improve 
the value of the diagrams, by incorporating four simplified diagrams 
instead of two.
    (3) Table 3 of NEMA TP 2 lacks a descriptive title, the title of 
Table 3's first column should be ``Resistance to be Measured,'' and the 
titles of the remaining three columns should each be followed by the 
word ``Method.'' In addition, Table 3's identification of the ranges 
covered by various methods does not reflect the capabilities of modern 
instruments. Resistance meters are available to measure resistances on 
a four-terminal basis below 10 ohms, and voltmeter-ammeter methods are 
useable above 100 ohms. Hence, today's proposed rule does not contain a 
table that is a counterpart to Table 3, and but instead sets forth in 
narrative form the approximate ranges for the use of each method.
    (4) Equation (2) for phase angle correction, in section 4.1.4 of 
NEMA TP 2, is incorrect. The equation should be Pc = Pm - VmAm (Wd - Vd 
+ Cd ) sin f, where f = cos-1(Pm/VmAm). Also, NEMA TP 2 
fails to define the polarities of the phase angle errors. For example, 
Wd is positive if the phase angle between the voltage and current 
phasors as sensed by the wattmeter is smaller than the true phase 
angle. The Department believes that today's proposed test procedure 
correctly addresses these points based on the provisions of IEEE 
C57.12.90 and C57.12.91. The Department also notes that, although 
equation (4-3) in section 4.5.3.2 of the proposal does not appear in 
the IEEE standards, it provides information similar to that in Table 1 
of

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the IEEE C57.12.90 as to whether phase angle correction is required.
    (5) Section 4.3.4.2 of NEMA TP 2 lacks some of the steps needed to 
calculate the load loss from the previously measured quantities. The 
test procedure proposed in today's notice includes all of the necessary 
steps.
2. Reference Conditions
    To establish a standard basis for test results, today's proposed 
test procedure specifies reference conditions for testing and rating 
the efficiency of distribution transformers. In particular, the test 
procedure would require that equipment efficiencies be rated at the 
loading levels of 35 percent for low-voltage, dry-type models and 50 
percent for medium-voltage, dry-type and all liquid-immersed models, as 
specified in NEMA TP 2.
    The Department recognizes that considerations other than efficiency 
commonly require manufacturers to test transformers at 100 percent of 
their rated load. Today's proposed test procedure includes analytical 
techniques that a manufacturer could use, where it has tested a 
transformer at 100 percent of its rated load, to calculate the 
transformer's efficiency at the loading point specified in the test 
procedure. Thus, the manufacturer would not have to test the 
transformer at both the loading point prescribed in the test procedure 
and at 100 percent of its rated load. Moreover, once today's test 
procedure has been implemented, should experience indicate that the 
loading levels specified in the test procedure are not appropriate for 
rating some distribution transformers, the Department would consider 
adopting different loading levels for those types of transformers.

B. Transformers Subject to the Test Procedure

1. Background
    In essence, section 346 of EPCA directs the Department to consider 
whether an energy conservation program for ``distribution 
transformers'' is warranted. (42 U.S.C. 6317(a)(1)) However, the 
statute does not define ``distribution transformer.'' In the 
Determination notice, the Department interpreted the term 
``distribution transformer'' in section 346 of EPCA to mean ``all 
transformers with a primary voltage of 480 V to 35 kV, a secondary 
voltage of 120 V to 480 V, and a capacity of either 10 to 2500 kVA for 
liquid-immersed transformers or 0.25 kVA to 2500 kVA for dry-type 
transformers,'' except for transformers which are not continuously 
connected to a power distribution system as a distribution transformer. 
62 FR at 54811. The 1998 proposal proposed to adopt essentially this 
same definition, except that the upper limit on secondary voltage was 
increased from 480 V to 600 V because the Department learned that 
industry typically classifies transformers with a secondary voltage up 
to 600 V as distribution transformers. 63 FR 63370 (November 12, 1998).
    The primary reason for defining distribution transformer in this 
rulemaking is to identify the transformers to which the Department's 
test procedure would apply. As indicated above, initially the test 
procedure would apply only to those transformers that the Department is 
evaluating for standards. Thus, the issue of which products should be 
within today's proposed definition of distribution transformer is 
identical to the issue of which products the Department will evaluate 
for standards. As the following discussion indicates, in developing 
this definition, the Department has considered information received in 
its rulemaking on transformer standards. The Department has also based 
the proposed definition on consideration of the nature of transformers 
that are commonly understood to be ``distribution transformers,'' and 
of whether energy conservation standards for such a transformer would 
result in significant energy savings.
2. Changes to, and Retention of, Provisions in the 1998 Poposed Rule
    Today's proposal eliminates from the definition of distribution 
transformer the 1998 proposed rule's lower limits on primary voltage 
and secondary voltage of 480 V and 120 V, respectively. In the 1999 
reopening notice, the Department stated that it did not intend to 
increase the lower limit on primary voltage to 600 V. 64 FR at 33432-
33. In the proceedings on the development of standards, NEMA strongly 
advocated that the Department have no lower limits on the primary and 
secondary voltages of the transformers it evaluates for standards, 
reflecting the coverage of NEMA TP 1. (NEMA, No. 35 at p. 4 and No. 36 
at p.2) \5\ Consistent with NEMA's position, the Department is 
concerned that defining a distribution transformer as having a minimum 
primary and/or secondary voltage may result in eliminating distribution 
transformers from consideration in the standards rulemaking. The 
Department also believes that it can include other elements in its 
definition of ``distribution transformer'' to ensure that its test 
procedures and standards for transformers would cover only products 
that are truly ``distribution transformers.'' Therefore, in accordance 
with its planned approach in the standards rulemaking, and to ensure 
that its test procedure will apply to all distribution transformers 
evaluated for standards, the Department has removed the lower bounds on 
primary and secondary voltage from the definition of distribution 
transformer that the Department is proposing today.
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    \5\ No. 35 and No. 36 refer to the numbers of the written 
comments and supporting documents included or referenced in the 
docket for this rulemaking (Docket Number EE-TP-98-550). Numbers 4 
and 2 refer to the cited page numbers in those written comments.
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    With regard to the 1998 proposed rule's capacity criteria for 
defining a distribution transformer (10 kVA to 2500 kVA for liquid-
immersed units and 0.25 kVA to 2500 kVA for dry-type units), the 1999 
reopening notice stated the Department's intent to increase the lower 
capacity limit for dry-type units to either 1, 5, 10 or 15 kVA. 64 FR 
at 33433. The Department understands, based on information it has 
received in the course of its work on the standards rulemaking, that 5 
and 10 kVA dry-type transformers are normally not used in the 
distribution of electric energy. Therefore, today's definition of 
distribution transformer proposes a lower capacity limit for dry-type 
units of 15 kVA. The Department, however, is still considering in the 
standards rulemaking whether to evaluate for standards dry-type 
transformers with ratings of 5 and 10 kVA. Therefore, DOE seeks comment 
in the instant rulemaking on whether such transformers are properly 
classified as distribution transformers, and whether it should adopt 
one of these levels as the lower capacity limit for dry-type units in 
the definition of distribution transformer, instead of the 15 kVA level 
in today's proposed rule.
    The 1998 proposed rule's definition also excluded ``transformers 
which are not designed to be continuously connected to a power 
distribution system as a distribution transformer * * * [such as 
certain specifically identified types of transformers] and other 
transformers which are not designed to transfer electrical energy from 
a primary distribution circuit to a secondary distribution circuit, or 
within a secondary distribution circuit, or to a consumer's service 
circuit.'' 63 FR at 63370. The Department is concerned that these 
criteria may be too vague and imprecise, and subject to 
misinterpretation, and may fail to establish clearly which transformers 
are and are not covered under EPCA as

[[Page 45510]]

distribution transformers. This would be particularly true for parties 
that work with distribution transformers in non-utility related 
applications, where much of the terminology in these criteria--for 
example, phrases like ``to a consumer's service circuit''--is 
inapplicable and may be meaningless. In the standards rulemaking, NEMA 
has advocated that the Department adopt a definition of distribution 
transformer that aligns with the scope of NEMA TP 1. (NEMA No. 35 at p. 
4) The scope provision of NEMA TP 1 states that the standard applies to 
transformers meeting numerical criteria of the types discussed above--
for example, capacity in kVA--and then lists specific types of 
transformers to which the standard does not apply. (NEMA TP 1 at p. 1)
    Today's proposed rule follows this approach in defining 
distribution transformer and is similar to the scope provision of NEMA 
TP 1. In addition to having numerical criteria, the proposed definition 
lists types of transformers that are made for applications unrelated to 
the distribution of electricity, or for which standards would not 
produce significant energy savings, and provides that they are not 
``distribution transformers.'' Such a definition is clearer, more 
precise and less subject to misinterpretation than the 1998 proposed 
rule's definition. Although the list of excluded transformers is quite 
similar to that in NEMA TP 1, DOE has modified it slightly.\6\ The 
proposed rule also contains a definition for each of these excluded 
transformers.
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    \6\ Today's proposed definition of ``distribution transformer'' 
excludes almost verbatim 13 of the 17 types of transformers 
specifically excluded from NEMA TP 1. (The list of exclusions from 
TP 1 appears on page one of TP 1.) NEMA TP 1, however, also excludes 
``transformers designed for high harmonics'' and ``harmonic 
transformers,'' but today's proposed definition addresses these 
transformers by excluding ``harmonic mitigating transformers'' and 
certain ``K-factor'' (harmonic tolerating) transformers. In 
addition, although TP 1 excludes ``retrofit transformers'' and 
``regulation transformers,'' the proposed rule excludes neither--the 
former for reasons discussed in section II-B-3 in the text and the 
latter because DOE believes they are more accurately described as 
``regulating transformers,'' which are already in the list of 
exclusions in NEMA TP 1 and the proposed rule. In addition, NEMA TP 
1 excludes ``non-distribution transformers, such as UPS 
[uninterruptible power supply] transformers.'' Although the proposed 
definition excludes uninterruptible power supply transformers, the 
remainder of this exclusion is vague, and the Department believes 
that including it in the regulations would undercut the precision 
achieved by listing specific types of transformers as being excluded 
from the definition of ``distribution transformer.''
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    The 1998 proposed rule identified the following transformers as not 
being distribution transformers: grounding transformers, machine-tool 
(control) transformers, regulating transformers, testing transformers, 
and welding transformers. 63 FR at 63370. They were not addressed 
further in either the comments DOE received in this rulemaking or the 
1999 reopening notice and they are listed as exclusions in the scope 
provision of NEMA TP 1. For all of these reasons, they are excluded 
from being ``distribution transformers'' in today's proposed rule.
    The 1998 proposed rule also excluded ``converter and rectifier 
transformers with more than two windings per phase'' from the 
definition of distribution transformer, and provided definitions for 
these transformers. 63 FR at 63370. Comments on the 1998 proposed rule 
and the 1999 reopening notice supported these exclusions, as well as 
the exclusion of rectifier transformers with less than three windings. 
(Alexander D. Kline, P.E., No. 14 at pp.1-2; NEMA, No. 15 at p. 2, No 
21 at p. 5, and No. 28 at p. 5; Howard Industries, Inc., No. 18 at p. 3 
and No. 27 at p. 2) The Department now believes that exclusion of 
converter transformers is unnecessary. Today's proposed definition of 
distribution transformer has an upper limit on capacity of 2500 kVA, 
and it is the Department's understanding that a transformer connected 
to a converter, i.e., a converter transformer, always has a capacity 
far above this level. Thus, their capacity automatically excludes them 
from the definition, and they need not be specifically excluded. 
Rectifier transformers, however, often have a capacity below 2500 kVA, 
but they are not connected to electric distribution systems and cannot 
be readily tested for losses. See 64 FR at 33433 (and comments cited 
there) and 63 FR at 63363. Therefore, in today's proposed rule they are 
in the list of products not included as distribution transformers. The 
Department is also proposing to adopt the definition of ``rectifier 
transformer'' that was recently incorporated into IEEE C57.12.80-2002, 
clause 3.379, rather than the definition proposed in the 1998 proposed 
rule. The Department believes the IEEE definition will be more widely 
understood and accepted, without any loss of technical precision.
3. Exclusions Discussed in the 1999 Reopening Notice
    The 1999 reopening notice stated that the Department was also 
inclined to exclude autotransformers, and transformers with tap ranges 
greater than 15 percent, from the definition of distribution 
transformer. 64 FR at 33433-34. The notice identified comments on the 
1998 proposed rule that advocated these exclusions and the Department's 
reasons for favoring them. Some of the comments in response to the 
reopening notice supported the exclusions and none opposed them. 
Therefore these exclusions are included in today's proposed rule.
    The Department also discussed in the 1999 reopening notice whether 
it should exclude sealed or non-ventilated transformers, special 
impedance transformers, and harmonic transformers from the definition 
of distribution transformer. 64 FR at 33433-34. Each of these types of 
transformer can be a distribution transformer. The Department stated 
that it did not find persuasive the reasons commenters had advanced for 
excluding these products, and that it intended to include them unless 
it received information justifying their exclusion. As to non-
ventilated or sealed transformers, in response to the 1999 reopening 
notice NEMA indicated that the unique features of these transformers 
could pose a hardship for some manufacturers in testing them, and that 
they are a small part of the market for distribution transformers. 
(NEMA, No. 28 at p. 5) Given their small market share, it appears that 
adopting standards for non-ventilated or sealed transformers would not 
result in significant energy savings. For these reasons, the Department 
has excluded them from today's proposed definition of distribution 
transformer. DOE specifically requests comment, however, on whether 
such exclusion is warranted.
    With respect to special impedance distribution transformers, NEMA 
states that they have much higher load losses than standard impedance 
distribution transformers, and are designed to meet unusual performance 
functions. (NEMA, No. 28 at p. 5) It also asserts that, because they 
are relatively expensive to build, a lack of Federal efficiency 
standards for these products would not cause them to be manufactured 
and sold in increased volumes as substitutes for standard distribution 
transformers that were subject to standards. (NEMA, No. 15 at p. 2) The 
Department agrees with these points, and believes that the market for 
these products is small and therefore regulating them would not result 
in significant energy savings. For these reasons, today's proposed rule 
excludes special impedance transformers from the definition of 
distribution transformer.
    DOE questions, however, the validity of NEMA's claim that any 
transformer with an impedance outside the range of four to eight 
percent is a special impedance transformer. (NEMA, No. 15 at p. 2) To 
address this issue, the Department is proposing a definition for

[[Page 45511]]

``special impedance transformer'' that incorporates tables which set 
forth the normal impedance range at each standard kVA rating for 
liquid-immersed and dry-type transformers. DOE would consider any 
transformer built with an impedance rating outside the ranges defined 
as normal to be considered special impedance, and would exclude it from 
the definition of distribution transformer. The Department specifically 
requests comments on the normal impedance ranges shown in Tables 1 and 
2 of today's proposed definition of ``special impedance transformer.''
    Concerning harmonic distribution transformers, the Department 
understands that there are two types of such transformers, those that 
correct harmonics (harmonic mitigating transformers) and those that 
simply tolerate, and do not correct, harmonics (called harmonic 
tolerating or K-factor transformers). NEMA appears to assert that 
neither type can be accurately tested to measure its efficiency. (NEMA, 
No. 28 at p. 5) Although the Department has doubts about the validity 
of this assertion, it agrees that harmonic mitigating transformers are 
a special type of transformer. Furthermore, DOE believes that few of 
them exist in the distribution system, regulating them would save 
little energy, and they are sufficiently expensive to manufacture that 
excluding them would be unlikely to result in a loophole if DOE adopted 
standards for other transformers. DOE is, therefore, excluding harmonic 
mitigating transformers from coverage in today's proposed rule.
    The situation with harmonic tolerating (K-factor) transformers is 
not so clear cut. These transformers are designed for use in industrial 
situations where electronic apparatus can cause transformer losses that 
are much higher than normal, and they are designed to accommodate such 
losses without excessive temperature rise. But apparently it is 
economically viable to use K-factor distribution transformers that have 
low K-factors and relatively low efficiencies, in standard 
applications, instead of regular distribution transformers with higher 
efficiencies. The Department understands that, after the State of 
Minnesota began to require that dry-type distribution transformers 
installed in the state meet NEMA TP 1 efficiency levels, with an 
exemption for K-factor and other transformers excluded from NEMA TP 1, 
the installation of K-4 transformers increased substantially. These K-4 
transformers had efficiencies that were not only below the levels 
mandated by NEMA TP 1, they were also below the prevailing efficiency 
levels of conventional distribution transformers that had been 
installed in Minnesota prior to the State's adoption of NEMA TP 1. As 
the K rating of K-factor transformers increases, however, they become 
increasingly sophisticated and expensive to produce, and their market 
share decreases. Thus, the risk that they would be used in place of 
more efficient transformers declines, and the potential energy savings 
from regulating them becomes insignificant.
    The Department believes that K-13 is a reasonable demarcation 
between K-factor distribution transformers that should be evaluated for 
standards, and those for which standards appear to be unwarranted. 
Above the K-4 rating, K-9 and K-13 are the next higher standard K-
factor rated transformers. The Department believes that while K-9 
products are a small part of the market, it is uncertain whether, 
absent standards for them, K-9 distribution transformers would be 
substituted for transformers that are subject to standards (as happened 
in Minnesota with K-4 transformers). The Department is aware that K-
factor transformers at K-13 and higher are significantly more expensive 
than conventional transformers, and believes it is very unlikely they 
would be purchased in place of distribution transformers subject to 
standards. Thus, today's proposed definition excludes transformers with 
a K-factor rating of K-13 or higher from the definition of a 
distribution transformer. The definition includes K-factor transformers 
with lower standard K-factors (K-4 and K-9), and DOE is evaluating them 
for standards during its rulemaking on transformer standards. The 
Department specifically invites comments on this issue.
    Finally, information developed thus far in this proceeding 
indicates that ``retrofit distribution transformer'' refers to any 
transformer that replaces an existing distribution transformer. The 
Department understands, however, that the term also may refer more 
specifically to a transformer used in a distribution substation between 
primary and secondary switchgear 30 to 50 years old, which must be 
designed so that terminations are compatible with existing switchgear 
and for which other features must differ from present-day designs. 
Comments on the 1998 proposed rule asserted that the Department's 
exclusions from the definition of distribution transformer should 
provide for situations where existing distribution transformers cannot 
be replaced with more efficient retrofit transformers, which generally 
would be larger than, or configured differently from, the existing 
transformers. (NEMA, No. 21 at pp. 5-6) In the 1999 reopening notice 
the Department requested further, more detailed information on this 
issue. 64 FR at 33434. The Department has not received such 
information. Clearly retrofit distribution transformers are 
distribution transformers, and the Department lacks a basis for 
creating an exclusion for them in today's rule. In the standards 
rulemaking, however, the Department intends to gather information on 
the nature of, and dimensional restrictions for, these transformers, in 
order to decide whether to treat them separately, as for example by 
excluding them, by creating a separate class(es) or both, if the 
Department adopts energy conservation standards for distribution 
transformers.
4. Additional Exclusions Drawn From NEMA TP 1
    In addition to excluding from its scope the types of transformers 
discussed in sections II-B-2 and 3, NEMA TP1 also excludes drive 
(isolation), traction-power, and uninterruptible power supply 
transformers. Drive or isolation transformers are a type of 
distribution transformer that is specially designed to accommodate 
added loads of drive-created harmonics, and mechanical stresses caused 
by an alternating current or direct current motor drive. Although 
intrinsically they have higher losses than conventional distribution 
transformers, DOE understands that they also have low sales volumes. 
Therefore, the Department believes standards for this product would not 
result in significant energy savings and is proposing to exclude them 
from the definition of distribution transformer. In addition, the 
Department notes that there are many kinds of drive transformers, and 
development of the varied test methods and multiple standard levels 
that would be necessary to achieve even the limited energy savings 
possible for this product would be a complex undertaking.
    As to traction-power transformers, these are designed to supply 
power to railway trains or municipal transit systems, at frequencies of 
16\2/3\ or 25 Hz in an alternating current circuit or as a rectifier 
transformer. These transformers are excluded from today's proposed 
definition of distribution transformer by provisions discussed above 
that exclude both transformers operating at these low frequencies as 
well as rectifier transformers. Therefore, DOE need not consider 
whether to specifically exclude them.

[[Page 45512]]

    Finally, an uninterruptible power supply transformer is not a 
distribution transformer. It does not have as one of its functions 
stepping down voltage, but rather it is a transformer that is a system 
conditioning device. It is used as part of the electric supply system 
for sensitive equipment that cannot tolerate system interruptions or 
distortions, and counteracts such irregularities. Therefore, it is 
excluded from the definition of distribution transformer in today's 
proposed rule.
5. Definitions of Excluded Transformers
    As noted above, today's proposed rule includes definitions for the 
transformers DOE is proposing to exclude from today's rule. This will 
help to make clear exactly which transformers the proposed rule covers. 
For the following excluded transformers, DOE has taken the definitions 
from IEEE C57.12.80-2002: autotransformers, grounding transformers, 
machine-tool (control) transformers, non-ventilated transformers, 
rectifier transformers, regulating transformers, and sealed 
transformers. For K-factor transformers, DOE took the definition from 
Underwriters Laboratories (UL) UL1561 and UL1562.

C. Basic Model

    It is common for a manufacturer to make numerous models of a 
product covered by EPCA, and under the Act each model is potentially 
subject to testing for energy efficiency. In order to lessen the burden 
of testing, the Department allows manufacturers to group product models 
having essentially identical characteristics with respect to energy 
consumption into a single family of models. The Department has used the 
term ``basic model'' to represent such a family of models, consisting 
of models of a product that are essentially the same in some or all of 
the following respects: performance, physical, mechanical, electrical 
and functional characteristics. For each type of product, the 
Department's regulations set forth which of these characteristics 
applies in identifying basic models. Each manufacturer can then test a 
sufficient, representative sample of units of each basic model it 
manufactures, and derive an efficiency rating for each basic model that 
would apply to all models subsumed by that basic model. Components of 
similar design can be substituted in a basic model without requiring 
additional testing if the represented measures of energy consumption 
continue to satisfy applicable provisions for sampling and testing.
    At the 1998 workshop, DOE presented a basic model definition for 
distribution transformers that incorporated these concepts. All groups 
and individuals who participated in that workshop opposed DOE's 
proposed definition because distribution transformers, unlike consumer 
appliances, are not produced in large numbers of virtually identical 
units. NEMA advocated at the workshop that DOE define basic model to 
include all transformers having the same nominal power (kVA) rating, 
the same insulation type (liquid immersed or dry-type), and the same 
number of phases (single or three), and operating within the same 
voltage range. (Public Workshop Tr., No. 2GG at pp. 54-55) \7\ The 
Department proposed such a definition in the 1998 proposed rule. 63 FR 
at 63369. As the Department pointed out in the 1999 reopening notice, 
however, it later realized that this approach would allow a single 
basic model to include models of transformers that have significantly 
different utility or performance-related features that affect their 
efficiency. This would be inconsistent with the nature of the groupings 
that the ``basic model'' concept is meant to permit, since all models 
within a basic model should be in the same product class. 64 FR at 
33435.
---------------------------------------------------------------------------

    \7\ ``Public Workshop Tr., No. 2GG at pp. 54-55'' refers to the 
page number of the transcript of the ``Workshop on Test Procedures 
for Distribution Transformers'' held in Washington, DC on February 
10, 1998.
---------------------------------------------------------------------------

    All of the comments to the 1999 reopening notice that addressed the 
basic model definition supported the approach in the 1998 proposed 
rule, but none addressed DOE's concern that the 1998 proposed rule 
definition would permit inclusion of models with different energy 
consumption characteristics in any particular basic model. One comment 
stated that the proposed definition would be a sound way to reduce the 
testing burden on manufacturers. (Howard Industries, No. 27 at p. 3) 
DOE continues to believe that any definition of basic model under its 
regulations must require that all of the models included in a basic 
model have similar energy consumption characteristics and be within the 
same product class. This is necessary to assure that the efficiency 
rating derived for the basic model would accurately represent the 
efficiency of all of these models. The Department is therefore 
proposing a definition of basic model for distribution transformers 
that includes essentially the same criteria contained in the definition 
proposed in the 1998 proposed rule, plus a requirement that the 
transformers included in the basic model ``not have any differentiating 
electrical, physical or functional features that affect energy 
consumption.''
    Today's proposed definition includes two editorial modifications to 
the criteria included in the 1998 proposed rule definition. First, the 
proposed definition omits the provision that transformers within a 
basic model must ``operate within the same voltage range.'' This 
criterion need not be stated explicitly in the proposed definition 
because it is embodied in the new proposed requirement that 
transformers cannot have differentiating electrical features that 
affect energy consumption. Second, the provision in the 1998 proposed 
rule that all transformers in a basic model must ``have a comparable 
nominal output power (kVA) rating'' is replaced in today's proposed 
rule with language that they have ``the same standard KVA rating.'' Use 
of the word ``same'' instead of ``comparable'' better achieves the 
Department's intent in the 1998 proposed rule to require that all 
transformers in a basic model have the same standard kVA rating, an 
approach supported in comments on the 1998 proposed rule and 1999 
reopening notice. (NEMA, No. 28 at p. 7; Howard Industries, No. 18 at 
p. 3 and No. 27 at p. 3) In addition, the Department's understanding is 
that ``standard kVA rating'' means the same thing as ``nominal output 
power (kVA) rating.'' The former terminology is proposed here because 
it is more succinct and straightforward.
    Regarding the term ``standard kVA rating,'' the transformer 
industry normally groups transformers based on apparent power rating 
and over the years has developed a set of standard ratings, ANSI/IEEE 
C57.12.00-2000 for liquid-immersed transformers and ANSI/IEEE 
C57.12.01-1998 for dry-type transformers. These standard ratings are 
set forth in the table that follows, and are the ratings that the 
Department refers to when it uses the term ``standard kVA rating'' in 
today's proposed basic model definition. Thus, under today's proposal, 
grouping of distribution transformers into basic models would be based 
in substantial part on groupings already used by the transformer 
industry.

[[Page 45513]]



           Standard kVA Ratings for Distribution Transformers*
                                  [kVA]
------------------------------------------------------------------------
 
------------------------------------------------------------------------
                              Single phase
------------------------------------------------------------------------
10**............................................................     167
15..............................................................     250
25..............................................................     333
37.5............................................................     500
50..............................................................     667
75..............................................................     833
100.............................................................  ......
-----------------------------------------------------------------
                               Three phase
------------------------------------------------------------------------
15..............................................................     300
30..............................................................     500
45..............................................................     750
75..............................................................    1000
112.5...........................................................    1500
150.............................................................    2000
225.............................................................   2500
------------------------------------------------------------------------
* The Department anticipates that it will subdivide the kVA ratings for
  the medium-voltage dry-type distribution transformers by basic impulse
  insulation level (BIL) rating during the standards rulemaking process,
  and develop separate efficiency ratings for each BIL rating associated
  with each kVA rating for these transformers. This would not affect
  manufacturers' basic model delineations under today's proposed
  definition of basic model. By providing that a basic model cannot
  include transformers that have differentiating electrical features,
  the proposed definition would already require that transformers with
  different BIL ratings be separated into different basic models.
** 10 kVA is a standard rating for liquid-immersed distribution
  transformers, but not necessarily for dry-type transformers.

    The Department recognizes that any given manufacturer would likely 
have more basic models under today's proposed definition of basic model 
than under the 1998 proposed rule's definition. Potentially, this could 
increase the manufacturers' test burden. The Department believes, 
however, that this potential would be more than offset by its proposal, 
discussed below, to allow manufacturers to determine the efficiencies 
of a substantial number of their basic models by using alternative 
efficiency determination methods, instead of testing these basic 
models.

D. Manufacturer's Determination of Efficiency

    In developing proposed requirements for distribution transformers, 
the Department initially examined as a model its regulations for 
consumer appliances in 10 CFR part 430, and later also examined its 
regulations for electric motors in 10 CFR part 431, after it adopted 
them in late 1999. Under both parts 430 and 431, each manufacturer must 
determine the efficiency rating for each of its basic models, to a 
substantial extent from testing the model. (Such testing is commonly 
referred to as ``compliance testing.'') As just discussed, use of the 
``basic model'' concept is one means for reducing the potential 
compliance testing burden on manufacturers. The Department also reduces 
the compliance testing burden by allowing manufacturers to test a 
sample of units of each basic model. For each type of product, the 
regulations prescribe a statistical sampling plan designed to give a 
reasonable assurance that on average the performance of all units 
manufactured and sold of each basic model complies with (i.e., equals 
or exceeds) the manufacturer's rating for the model and the applicable 
energy conservation standard mandated under EPCA.
    In the 1998 proposed rule, the Department proposed to use part 
430's sampling approach for compliance testing, with numerical criteria 
geared to distribution transformers and a minimum sample size of five 
units. 63 FR at 63366-67. But this approach is not well suited to 
situations where only a very small test sample (fewer than five units, 
for example) is available, and therefore it could be problematic for 
some distribution transformers.\8\ Although some basic models of 
transformers are mass-produced, many are custom-designed with 
production runs of as few as one unit. Consequently, in the 1998 
proposed rule the Department sought comment on three alternative 
approaches for basic models with limited production. 63 FR at 63366-67.
---------------------------------------------------------------------------

    \8\ The operating characteristics of the proposed compliance 
plan were examined and reported in National Institute of Standards 
and Technology (NIST) Technical Note (TN) 1427, ``An Analysis of 
Efficiency Testing under the Energy Policy and Conservation Act: A 
Case Study with Application to Distribution Transformers'' (NIST TN 
1427). NIST TN 1427 noted for example that for a test sample of two 
units of a basic model that is designed and performing at a given 
rated value, and has a standard deviation of three percent, the 
probability of demonstrating compliance with that rated value is 
only about 0.12, and the probability of a false conclusion of 
noncompliance is about 0.88.
---------------------------------------------------------------------------

    In response to the 1998 proposed rule, industry representatives 
commented that the proposed sampling plan might require manufacturers 
to do a large amount of testing, and, as DOE had indicated in the 1998 
proposed rule, the plan appears unsuitable for basic models with small 
production volumes. (Public Meeting Tr., No. 11DD at p. 174; Howard 
Industries, No. 18 at p.5) \9\ None of the comments, however, addressed 
the alternatives DOE had presented for dealing with these small 
production models. See 64 FR at 33434. NEMA advocated that DOE adopt 
the sampling plan set forth in NEMA TP 2, significant elements of which 
are (1) on-going testing during 180-day periods of either 100 percent 
of the units manufactured or a random sample of a statistically valid 
number of units (but not less than five per month), (2) discarding or 
reworking all tested units that exceed losses allowed under the 
applicable standard by more than eight percent,\10\ and (3) for each 
180-day period, aggregating the test results of different basic models 
(comprising all or a portion of a manufacturer's production) to 
determine their collective compliance with the applicable standards.
---------------------------------------------------------------------------

    \9\ ``Public Workshop Tr., No. 11DD at pp. 54-55'' refers to the 
page number of the transcript of the ``Public Hearing on Energy 
Efficiency Test Procedures--Distribution Transformers'' held in 
Washington, DC on January 6, 1999.
    \10\ For transformers, the industry practice is to measure power 
loss and evaluate performance in terms of such losses. Performance 
is expressed in terms of efficiency only at the final stage of 
rating the product.
---------------------------------------------------------------------------

    In the 1999 reopening notice, the Department expressed concern 
about aggregation as used in NEMA TP 2, particularly for basic models 
produced in relatively large volumes (50 or more in a six-month 
period). In DOE's view, compliance of the large volume models could be 
demonstrated without aggregation. But the Department stated that 
aggregation combined with testing all of the units of a basic model has 
some merit, particularly for limited production models. Therefore, DOE 
identified for consideration several alternatives to the proposal in 
the 1998 proposed rule, including variations on NEMA TP 2 that would 
allow manufacturers to demonstrate the compliance of aggregations of 
basic models subject to certain conditions. 64 FR at 33434-35. The goal 
of these alternatives was to provide a reasonable statistical method 
for deriving efficiency ratings from test results that would minimize 
the risk of false negatives for small volume basic models, i.e., would 
make it unlikely that a manufacturer would determine a complying basic 
model to be out of compliance. The Department indicated, however, that 
although some of these options may be sufficient to assure compliance 
with efficiency standards by basic models that are included in 
aggregations, they may not be adequate to establish the validity of the 
represented efficiency level for particular basic models.
    The comments on the 1999 reopening notice generally supported DOE's 
adoption of the sampling plan in NEMA TP 2, with Howard Industries 
urging DOE to adopt an approach that would minimize the number of units 
that a manufacturer must test. (American Council for an Energy-
Efficient Economy, No. 29 at p. 3; Howard Industries, No. 27 at pp. 2-
3; NEMA, No. 28 at pp. 6-7). None of the comments, however, addressed 
the

[[Page 45514]]

alternatives DOE had presented in the reopening notice that would allow 
for aggregation of basic models. NEMA essentially reiterated its view 
that the Department should adopt the sampling plan in NEMA TP 2, but 
asserted in addition that the approach proposed in the 1998 proposed 
rule had only a 50-percent probability of accurately representing the 
mean efficiency level of all units of a basic model and was 
statistically unsound. (NEMA, No. 28 at pp. 6-7)
    Upon consideration of the comments in this proceeding, and a 
further review of the sampling plan in NEMA TP 2, the Department 
continues to believe that NEMA TP 2's sampling plan is inappropriate 
for adoption as a DOE requirement. DOE has done considerable analysis 
of this issue since issuing the 1998 proposed rule. The Department's 
key concern regarding NEMA TP 2's sampling plan is the aggregation of 
test results. NEMA TP 2 allows a manufacturer to aggregate the test 
results of all or any portion of its basic models to determine their 
compliance with applicable standards. (The NEMA TP 2 sampling plan 
could also be used to determine compliance with rated efficiencies.) 
All of the basic models included in an aggregate grouping would be 
deemed to be in compliance (with applicable rated efficiencies and/or 
standards) so long as their weighted average efficiency measured from 
testing is equal to or larger than the weighted average rated 
efficiency or standard that applies to them. Thus, in a group of basic 
models found in compliance under NEMA TP 2's sampling plan, some of the 
basic models could have efficiencies below their applicable levels so 
long as other models exceed their levels. The Department recognizes 
that NEMA TP 2's eight percent limitation on total losses for 
individual tested units would encourage manufacturers to produce each 
basic model at or above the applicable efficiency level, and would 
provide some assurance that each basic model complies with that level. 
However, given the variability inherent in the manufacture of 
distribution transformers, the Department believes such assurance would 
be of limited value.
    This approach is unacceptable to DOE for several reasons. First, 
the Department believes EPCA contemplates that each basic model of a 
distribution transformer must comply with the efficiency standard 
applicable to it, not that all or some other disparate grouping of 
models will comply on average with the applicable standards. Section 
346(a) of EPCA directs DOE to prescribe energy conservation standards 
for those distribution transformers for which the Department determines 
standards would save significant amounts of energy and would be 
technologically feasible and economically justified. (42 U.S.C. 
6317(a)) And section 346(f) in effect bars distribution of any 
transformer that does not conform to the standard applicable to it. (42 
U.S.C. 6317(f)) The Department believes these provisions preclude it 
from mandating use of the sampling plan in NEMA TP 2, under which a 
manufacturer could determine all or groups of its basic models to be in 
compliance on average with applicable standards, with limited assurance 
that any particular basic model complies.
    Second, NEMA TP 2's sampling plan does not provide a sufficient 
basis for a manufacturer to make representations as to the efficiency 
of individual basic models. Section 346(d) of EPCA requires the 
Department to prescribe efficiency labeling requirements for the 
distribution transformers for which DOE prescribes standards. (42 
U.S.C. 6317(d)) Although the statute does not specify the content of 
such requirements, for other products the statute requires: (1) 
Efficiency labels that are based on or include the energy efficiency of 
the model on which the label appears, (see 42 U.S.C. 6293(b)(4), 
6294(c), and 6315(d)-(e)) and (2) that any energy use or efficiency 
representation by a manufacturer or other distributor ``fairly 
discloses'' the results of testing the product under the DOE test 
procedure (42 U.S.C. 6293(c) and 6314(d)). In addition, for consumer 
products and electric motors, DOE requires manufacturers to certify to 
the Department the efficiency or energy use of particular basic models 
that are covered by energy conservation standards. 10 CFR 430.62 and 
431.123. In 10 CFR 430.24 and 431.24, DOE provides the basis for 
manufacturers to comply with these requirements, by prescribing 
sampling plans and other methods for manufacturers to rate each basic 
model they produce. As indicated above, however, because of the 
aggregation of test results it contemplates, the sampling plan in NEMA 
TP 2 could not be used to establish the efficiency of any particular 
basic model. If the Department were to prescribe this sampling plan for 
distribution transformers, it would in effect be precluded from 
adopting for this product labeling and other energy representation 
requirements based on the energy use or efficiency of particular basic 
models, since no uniform basis would exist for assuring the accuracy of 
such representations. This would represent a considerable departure 
from the requirements for other products, and the Department believes 
it would be inconsistent with the intent of EPCA's labeling 
requirements.
    Third, the NEMA TP 2 sampling provisions are problematic when one 
considers the enforcement of efficiency standards and of labeling 
requirements. On the one hand, in an enforcement action the Government 
assesses whether a basic model is out of compliance with its labeled 
efficiency or the applicable standard. NEMA TP 2 contemplates, however, 
that a manufacturer could distribute a non-compliant basic model 
provided the manufacturer included other ``overly compliant'' models in 
an aggregation with the non-compliant model. The Department believes 
this inconsistency in approaches is unacceptable. On the other hand, it 
could be argued that DOE should align the enforcement provisions for 
distribution transformers with NEMA TP 2's sampling plan. This would 
mean that any enforcement action would have to concern all of the basic 
models included in an aggregation that the manufacturer had used to 
establish compliance, possibly including the manufacturer's entire line 
of products. The Department strongly believes that such an approach 
would be untenable, and that it should address its enforcement efforts 
to individual basic models alleged to be out of compliance, not batches 
of basic models.
    Finally, NEMA TP 2 contemplates more compliance testing than either 
part 430 or part 431. The sampling plan under part 430 prescribes no 
minimum size for a test sample, and the minimum sample size under part 
431 is five units. Under NEMA TP 2, a manufacturer must do continuous 
testing either of 100 percent of the units it manufactures or of a 
random sample of a statistically valid number of units (but not less 
than five per month). Manufacturers are of course free to voluntarily 
do any amount of testing they deem necessary to meet their own 
contractual and other business requirements. DOE is reluctant, however, 
to require this amount of testing, and to impose this burden as a legal 
mandate.
    For the foregoing reasons, the Department is not proposing to adopt 
the sampling plan in NEMA TP 2. Nevertheless, the Department agrees 
with NEMA that the sampling plan proposed in the 1998 proposed rule, 
using a methodology similar to that in 10 CFR part 430, could impose a 
significant risk of false negatives, i.e., compliant basic models found 
to be non-compliant. The Department

[[Page 45515]]

recognizes that there are inherent differences between the products 
regulated in part 430 and distribution transformers, and that these 
differences warrant a sampling plan for distribution transformers that 
is different from that in part 430. Manufacturers of electric motors 
had similar concerns, and DOE adopted a new sampling plan for 
determining a motor's efficiency in 10 CFR part 431.
    DOE is proposing today to adopt both a sampling plan and 
alternative methods (other than actual testing) for manufacturers to 
use to determine the efficiency of distribution transformers, which are 
similar to requirements that DOE has prescribed for electric motors. 
Today's proposals are a substantial departure from the approaches 
proposed in the 1998 proposed rule and 1999 reopening notice. The 
Department believes they would require manufacturers to do 
substantially less testing than contemplated either by the earlier 
proposals or by NEMA TP 2, while at the same time ensuring that 
products comply with applicable efficiency standards.
    Today's proposed sampling plan is designed to have a significantly 
higher probability than the 1998 proposed rule proposal that a basic 
model would be found in compliance with its rated value where it is in 
fact manufactured at that value, without incurring a probability for 
significant false positives, i.e., non-complying models being found in 
compliance. Similar to the sampling plan for motors, today's proposal 
is predicated on the principle that the mean power loss of the sample 
must be equal to or smaller than the rated loss plus five percent of 
the rated loss divided by the square root of the number of units in the 
sample. This translates into the ``Represented Efficiency'' expression 
in today's proposed section 432.12. The tolerance of the motors plan is 
constant, however, while that of today's proposed plan decreases with 
increases in the sample size. The motors plan also has an additional 
requirement that the power loss of a single unit in the sample must not 
exceed the rated loss by more than 15 percent. Today's plan includes no 
such provision in large part because the tolerance in today's proposal 
decreases with increased sample size. The proposed plan provides the 
same probability of demonstrating compliance for all sample sizes for a 
basic model that is manufactured at the rated efficiency. Finally, 
because the confidence limit varies with the standard deviation of the 
population, under the proposed plan a very high probability exists that 
complying basic models that have relatively small variabilities would 
pass compliance testing, i.e., be found in compliance with their rated 
values. For example, there is a 96.8 percent probability that a 
complying basic model with a standard deviation of 2.7 percent would 
pass compliance testing. Therefore, the manufacturer of such a basic 
model could design and manufacture the product at very close to its 
rated value, with little risk that it would fail compliance testing. A 
more thorough analysis of today's proposed sampling plan is set forth 
in NIST Technical Note 1456, ``Operating Characteristics of the 
Proposed Sampling Plans for Testing Distribution Transformers,'' which 
has been placed in the docket for this rulemaking and is publicly 
available at http://www.eere.energy.gov/buildings/appliance_standards/commercial/dist_transformers.html.
    Today's proposed sampling plan also would limit the testing burden 
on manufacturers. As with the motors plan, it prescribes a minimum test 
sample size of five units except when fewer than that number of units 
is manufactured in a 180-day period. It also handles samples as small 
as one.
    The key element that limits the test burden on manufacturers in 
today's proposed rule, however, is the proposal to allow manufacturers 
of distribution transformers to determine the efficiency of some of 
their transformers through use of alternative efficiency determination 
methods (AEDMs). An AEDM is a predictive mathematical model, developed 
from engineering analyses of design data and substantiated by actual 
test data, that represents the energy consumption characteristics of 
one or more basic models. Under today's proposal, after it 
substantiates the accuracy of an AEDM, the manufacturer can apply it to 
basic models to determine their efficiencies without testing them. The 
manufacturer would, however, have to determine the efficiency of at 
least five of its basic models, selected in accordance with criteria 
specified in the rule, through actual testing. The proposal would not 
permit a manufacturer to use the AEDM to rate any model that it had 
tested.
    Today's proposal requires a manufacturer to substantiate an AEDM 
based on actual testing of at least five basic models. (These could be 
the same five basic models just referred to.) The manufacturer would 
have to apply the AEDM to these basic models, and could use the AEDM to 
determine the efficiency of other basic models only if, (1) the 
predicted total power loss for each of these basic models, calculated 
by applying the AEDM, is within five percent of the mean total power 
loss determined from the testing of that basic model, and (2) the 
average of the predicted total power loss for the tested basic models, 
calculated by applying the AEDM, is within three percent of the average 
of the total power loss determined from testing these basic models. In 
making this second determination, the manufacturer would calculate the 
average predicted power loss of each basic model as a percentage of the 
average measured power loss, which in turn it would treat as 100 
percent. This expression of power losses as percentages is necessary in 
order for the manufacturer to assign equal weight to each basic model 
used to substantiate the AEDM.
    The Department selected the above tolerances because the power loss 
predicted from an AEDM will differ from that predicted from testing 
sample units of a basic model, due to the variability of units within 
each model. The magnitude of such differences depends on the degree of 
variability, quantified as the standard deviation, and the sample size. 
As the number of units in each sample and the number of samples 
increases the difference between the calculated and measured values 
should decrease, but as a practical matter it never disappears. DOE 
understands that a difference on the order of one to three percent is 
the minimum that can be achieved. The maximum difference of plus or 
minus three percent proposed in today's rule is appropriate for 
populations consisting of at least five basic models with at least five 
units in each. This allowable difference is equal to the allowable 
measurement error in the test procedure specified in proposed section 
432.11. The higher five-percent tolerance permitted for any single 
basic model allows for situations where units of a basic model have 
unusually high variability resulting in a relatively high standard 
deviation of four percent. This can result from factors such as 
variation in the materials used to produce the basic model and 
variability in the manufacturing process. Such factors can affect an 
entire production run for the basic model.

E. Enforcement Procedures

    As it did in developing proposals for manufacturers to rate the 
efficiency of distribution transformers, DOE reviewed the provisions of 
10 CFR parts 430 and 431 in formulating proposed enforcement procedures 
for this product. Parts 430 and 431 contain enforcement provisions that 
apply when DOE examines whether a basic model of a covered product 
complies with

[[Page 45516]]

efficiency requirements set forth in those parts. Each part allows for 
enforcement testing where necessary, and each includes a sampling plan 
for such testing. Neither the 1998 proposed rule nor the 1999 reopening 
notice addressed enforcement. The Department believes, however, that it 
is desirable to consider methods for manufacturers to use to rate their 
distribution transformers, and methods for enforcement testing, in 
conjunction with one another. Therefore, today's proposal includes 
proposed enforcement procedures, including a sampling plan and other 
provisions for enforcement testing. Substantial elements of these 
procedures are drawn from part 431 and their application to 
distribution transformers should not be controversial, but the 
Department nevertheless welcomes comment on them. However, the 
provisions as to the number of units to be tested and the number of 
tests to be performed are not drawn from part 431, and the sampling 
plan was developed specifically for application to distribution 
transformers. These provisions reflect the fact that some basic models 
of distribution transformers are produced in limited quantities. The 
Department is particularly interested in receiving comments on these 
provisions.
    The proposed enforcement sampling plan establishes detailed 
procedures for an enforcement action, and is similar to the enforcement 
sampling plans established in parts 430 and 431. All of these plans are 
based on a well established statistical method for obtaining a 
confidence interval on a mean, which first originated in Charles Stein, 
A Two-sample Test For a Linear Hypothesis Whose Power is Independent of 
Variance, 16 Annals of Mathematical Statistics 243-258 (1945). This 
procedure is discussed in Peter J. Bickel and Kjell A. Doksum, 
Mathematical Statistics: Basic Ideas and Selected Topics 158-159 
(1977), for example. The sampling plan for enforcement testing included 
in part 430 covers both efficiency and energy consumption, and it is 
general. The enforcement sampling plan proposed here, in Appendix B to 
proposed part 432, has been adapted from part 430, but has been 
simplified to address only efficiency testing. It also includes 
provisions to allow tests of very small samples. These provisions 
assure consistency with today's proposed sampling plan for compliance 
testing, discussed above.
    The proposed enforcement sampling plan is based on a t-test. The 
Department believes that the t-test is well suited for use in 
enforcement testing in that: (1) The t-test is insensitive to the exact 
nature of the distribution of performance of the item being evaluated, 
and (2) the risk of a false finding against a manufacturer can be set, 
by design, to a negligible level.
    The nature of the distribution of efficiency performance may be at 
issue for some basic models of distribution transformers. Some of them 
are produced in small quantities, and it is difficult to establish with 
confidence an accurate distribution of efficiency performance for very 
small test samples. Moreover, even some basic models produced in 
relatively large quantities may not have a normally distributed 
efficiency performance. Although the t-test assumes a normal 
distribution, it is insensitive to departures from that assumption. The 
t-test is a test on a sample mean that is an average of independent 
values obtained from a random sample. Since sums of arbitrary, 
independent random values tend to have a distribution that is almost 
normal, i.e. is very close to normal, even if the values themselves are 
not normally distributed, the t-test is not strongly influenced by the 
exact form of the underlying distribution of these values (in this case 
transformer efficiencies).
    Under parts 430 and 431, the test results obtained during 
enforcement testing may result in serious adverse actions against a 
manufacturer. For example, the manufacturer must cease distribution and 
sale of any basic model that the Department finds to be out of 
compliance, and the Department can assess a civil penalty for such 
noncompliance. Thus, the risk to a manufacturer of a false 
determination of noncompliance during an enforcement action is set, by 
design, to a negligible level. Today's proposed sampling plan for 
enforcement is based on a 97.5 percent statistical confidence, 
resulting in a risk of a false determination of noncompliance of not 
greater than 2.5 percent.
    As mentioned above, some basic models of distribution transformers 
may have limited production, and thus, few units may be available for 
testing. The proposed sampling plan for compliance testing contemplates 
that a basic model would be in compliance with its rated efficiency so 
long as the mean, measured efficiency of the compliance test sample of 
the basic model meets the following test:
[GRAPHIC] [TIFF OMITTED] TP29JY04.034

where RE is the rated efficiency and n is the number of units tested. 
Thus, the Department could find a basic model in compliance with its 
rated efficiency even if the mean efficiency of the test sample is less 
than the rated efficiency. This ``threshold efficiency'' establishes a 
reasonable lower control limit for compliance testing when very few 
units are available for testing.
    Under the proposed plan for enforcement testing, DOE would test a 
random sample and would calculate the mean, X, standard deviation, S, 
standard error in the mean, SE(X), and a sample size discount, SSD(m). 
In determining compliance with a rated efficiency, DOE would assume 
that the tested units are drawn from a population of transformers for 
which the mean efficiency is equal to or greater than the rated 
efficiency. Using the value for t at the 97.5 percentile of the t-
distribution for n tests, that is for n-1 degrees of freedom, the 
probability of obtaining a mean efficiency
[GRAPHIC] [TIFF OMITTED] TP29JY04.035

is not less than 97.5 percent. The procedure recommends a lower control 
limit,
[GRAPHIC] [TIFF OMITTED] TP29JY04.036

where the sample size discount,
[GRAPHIC] [TIFF OMITTED] TP29JY04.037

is included to be consistent with the provisions, just discussed, of 
the proposed plan for compliance testing. Here m is the number of units 
available for testing, which may not exceed 20 and can range between 1 
and 20 under the proposed provisions for enforcement testing. Provided 
the mean efficiency obtained from the random sample is not less than 
the lower control limit and the condition
[GRAPHIC] [TIFF OMITTED] TP29JY04.038

holds, the product is compliant.
    In any statistical test there is some probability of a false 
conclusion. Under the proposed sampling plan for enforcement, the 
probability that the mean efficiency for a random sample drawn from a 
compliant population of transformers would fall below the lower control 
limit, and hence the risk of incorrectly concluding that the basic 
model is in noncompliance, is not greater than 2.5 percent. 
Furthermore, if both the proposed compliance and enforcement plans were 
applied to the same sample test units, the risk of a false 
determination of noncompliance with a represented efficiency under the

[[Page 45517]]

proposed enforcement testing plan is not greater than 2.5 percent for 
units tested and found to be in compliance with that same represented 
efficiency under the compliance testing plan. Finally, as in parts 430 
and 431, today's proposed rule provides that after DOE determines a 
basic model to be in noncompliance through testing under the 
enforcement sampling plan, DOE will conduct additional testing if the 
manufacturer so requests, and such testing could result in a 
determination of compliance. This testing over and above that required 
under the enforcement sampling plan would further reduce the likelihood 
of a false determination of noncompliance and would thus allow a 
manufacturer to reduce the risk of a false conclusion.

F. New Part 432

    Section 346 of EPCA, 42 U.S.C. 6317, addresses energy conservation 
requirements for distribution transformers, high-intensity discharge 
lamps and small electric motors. As set forth in the 1998 proposed 
rule, 63 FR at 63367, the Department is proposing to add a new Part 432 
which would include efficiency regulations the Department adopts for 
these products. In this notice, the Department is proposing to adopt, 
and place in Part 432, regulations as to efficiency testing for 
distribution transformers. At such time as the Department adopts energy 
conservation standards and other requirements for distribution 
transformers, or requirements for high-intensity discharge lamps or 
small electric motors, it also intends to place them in Part 432.

III. Procedural Requirements

A. Review Under Executive Order 12866

    The Office of Information and Regulatory Affairs of the Office of 
Management and Budget (OMB) has determined that today's regulatory 
action is not a ``significant regulatory action'' under Executive Order 
12866, ``Regulatory Planning and Review,'' 58 FR 51735 (October 4, 
1993). Accordingly, this action was not subject to review under the 
Executive Order.

B. Review Under the Regulatory Flexibility Act

    The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires 
preparation of an initial regulatory flexibility analysis for any rule 
that by law must be proposed for public comment, unless the agency 
certifies that the rule, if promulgated, will not have a significant 
economic impact on a substantial number of small entities. As required 
by Executive Order 13272, ``Proper Consideration of Small Entities in 
Agency Rulemaking,'' 67 FR 53461 (August 16, 2002), DOE published 
procedures and policies on February 19, 2003, to ensure that the 
potential impacts of its rules on small entities are properly 
considered during the rulemaking process (68 FR 7990). DOE has made its 
procedures and policies available on the Office of General Counsel's 
Web site: http://www.gc.doe.gov.
    DOE reviewed today's rule under the provisions of the Regulatory 
Flexibility Act and the procedures and policies published on February 
19, 2003, and, for reasons that follow, certifies that the proposed 
rule, if adopted as a final rule, will not impose a significant 
economic impact on a substantial number of small entities.
    In another rulemaking, the Department is in the early stages of 
considering the adoption of mandatory energy conservation standards for 
distribution transformers. Today's proposed rule would prescribe test 
procedures that will be used to determine what standards, if any, DOE 
would adopt in that rulemaking, and it also contains certain related 
provisions. The proposed rule would likely become generally applicable 
only upon adoption of standards. Unless and until DOE adopts such 
standards, the Department anticipates that manufacturers will use the 
test procedures to voluntarily test their transformers and provide to 
DOE efficiency information about their products. But until energy 
conservation standards are adopted, no entities, small or large, would 
be required to comply with these test procedures, or with the other 
parts of today's proposed rule. Therefore, DOE believes today's 
proposed rule would not have a ``significant economic impact on a 
substantial number of small entities,'' and the preparation of a 
regulatory flexibility analysis is neither required nor warranted at 
this point.
    If the Department adopts standards for distribution transformers, 
DOE's regulations would require manufacturers to produce transformers 
that meet the standards. That requirement would have the effect of also 
requiring manufacturers to comply with the provisions in today's 
proposed rule (if it is subsequently adopted as a final rule), with 
respect to the distribution transformers that are subject to the 
standards. At that point, today's proposed rule would become binding 
on, and could have an economic impact on, small entities. But the 
nature and extent of any such impact cannot be assessed until the 
Department develops standards. Until then, neither the identity nor the 
proportion of distribution transformers covered by standards can be 
known. Since today's proposed rule would only be mandatory as to 
transformers covered by standards, only when that information is known 
will it be possible to determine what if any burdens the proposed rule 
would impose on small entities. In light of these circumstances, at an 
appropriate point in conjunction with the standards rulemaking, the 
Department will conduct further review under the Regulatory Flexibility 
Act.
    Accordingly, DOE has not prepared a regulatory flexibility analysis 
for this rulemaking. DOE will transmit the certification and supporting 
statement of factual basis to the Chief Counsel for Advocacy of the 
Small Business Administration for review pursuant to 5 U.S.C. 605(b).

C. Review Under the Paperwork Reduction Act

    Today's proposed rule contains certain record-keeping requirements. 
For example, proposed Sec.  432.12(a)(4)(ii) would require 
manufacturers to have records as to AEDMs available for DOE inspection, 
and proposed Sec.  6.0 of Appendix A to Subpart B would require 
maintenance of calibration records. But for the reasons explained in 
Section III. B. above, unless and until the Department requires 
manufacturers to comply with energy conservation standards for 
distribution transformers, no manufacturer would be required to comply 
with these record-keeping provisions. Therefore, today's notice of 
proposed rulemaking would not impose any new reporting requirements 
requiring clearance by OMB under the Paperwork Reduction Act, 44 U.S.C. 
3501 et seq.
    The Department recognizes, however, that if it adopts standards for 
distribution transformers, once the standards become operative 
manufacturers will become subject to the record-keeping requirements in 
today's proposed rule (if it has been adopted in a final rule). Prior 
to that time, therefore, these requirements, if covered by the 
Paperwork Reduction Act, must be reviewed and approved by OMB. In 
addition, in conjunction with proposing any standards for transformers, 
the Department may propose additional reporting and/or record-keeping 
requirements for this product that are similar to requirements already 
in place for consumer products in 10 CFR 430.62 and for electric motors 
in 10 CFR 431.123 and 431.124. Any such additional requirements also 
may be subject to clearance under the

[[Page 45518]]

Paperwork Reduction Act. The Department anticipates a Paperwork 
Reduction Act submission that will cover any such additional 
requirements and the information collection requirements in today's 
proposed rule.
    For these reasons, the Department will comply with the Paperwork 
Reduction Act with respect to the record-keeping requirements in 
today's rule at the appropriate point in conjunction with the standards 
development rulemaking. DOE nonetheless invites public comment on the 
collections of information proposed today.

D. Review Under the National Environmental Policy Act

    In this rulemaking, DOE proposes to adopt test procedures and 
related provisions for distribution transformers. The test procedures 
would be used initially for the purpose of considering the adoption of 
energy conservation standards for transformers, and DOE would require 
their use only if standards are subsequently adopted. The proposed test 
procedures will not affect the quality or distribution of energy and, 
therefore, will not result in any environmental impacts. DOE, 
therefore, determined that this rule falls into a class of actions that 
are categorically excluded from review under the National Environmental 
Policy Act of 1969 (42 U.S.C. 4321 et seq.) and the Department's 
implementing regulations at 10 CFR part 1021. More specifically, 
today's rule is covered by the Categorical Exclusion in paragraph A6 to 
subpart D, 10 CFR part 1021. Accordingly, neither an environmental 
assessment nor an environmental impact statement is required.

E. Review Under Executive Order 13132

    Executive Order 13132, ``Federalism,'' 64 FR 43255 (August 4, 1999) 
imposes certain requirements on agencies formulating and implementing 
policies or regulations that preempt State law or that have federalism 
implications. The Executive Order requires agencies to examine the 
constitutional and statutory authority supporting any action that would 
limit the policymaking discretion of the States and carefully assess 
the necessity for such actions. The Executive Order also requires 
agencies to have an accountable process to ensure meaningful and timely 
input by State and local officials in the development of regulatory 
policies that have federalism implications. On March 14, 2000, DOE 
published a statement of policy describing the intergovernmental 
consultation process it will follow in the development of such 
regulations (65 FR 13735). DOE has examined today's proposed rule and 
has determined that it does not preempt State law and does not have a 
substantial direct effect on the States, on the relationship between 
the national government and the States, or on the distribution of power 
and responsibilities among the various levels of government. No further 
action is required by Executive Order 13132.

F. Review Under Executive Order 12988

    With respect to the review of existing regulations and the 
promulgation of new regulations, section 3(a) of Executive Order 12988, 
``Civil Justice Reform'' (61 FR 4729, February 7, 1996), imposes on 
Federal agencies the general duty to adhere to the following 
requirements: (1) Eliminate drafting errors and ambiguity; (2) write 
regulations to minimize litigation; and (3) provide a clear legal 
standard for affected conduct rather than a general standard and 
promote simplification and burden reduction. Section 3(b) of Executive 
Order 12988 specifically requires that Executive agencies make every 
reasonable effort to ensure that the regulation: (1) Clearly specifies 
the preemptive effect, if any; (2) clearly specifies any effect on 
existing Federal law or regulation; (3) provides a clear legal standard 
for affected conduct while promoting simplification and burden 
reduction; (4) specifies the retroactive effect, if any; (5) adequately 
defines key terms; and (6) addresses other important issues affecting 
clarity and general draftsmanship under any guidelines issued by the 
Attorney General. Section 3(c) of Executive Order 12988 requires 
Executive agencies to review regulations in light of applicable 
standards in section 3(a) and section 3(b) to determine whether they 
are met or it is unreasonable to meet one or more of them. DOE has 
completed the required review and determined that, to the extent 
permitted by law, this proposed rule meets the relevant standards of 
Executive Order 12988.

G. Review Under the Unfunded Mandates Reform Act of 1995

    Title II of the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-
4) (UMRA) requires each Federal agency to assess the effects of Federal 
regulatory actions on State, local, and tribal governments and the 
private sector. With respect to a proposed regulatory action that may 
result in the expenditure by State, local and tribal governments, in 
the aggregate, or by the private sector of $100 million or more 
(adjusted annually for inflation), section 202 of UMRA requires a 
Federal agency to publish estimates of the resulting costs, benefits, 
and other effects on the national economy. (2 U.S.C. 1532(a), (b)) UMRA 
also requires a Federal agency to develop an effective process to 
permit timely input by elected officers of State, local, and tribal 
governments on a proposed ``significant intergovernmental mandate,'' 
and requires an agency plan for giving notice and opportunity for 
timely input to potentially affected small governments before 
establishing any requirements that might significantly or uniquely 
affect small governments. On March 18, 1997, DOE published a statement 
of policy on its process for intergovernmental consultation under UMRA 
(62 FR 12820) (also available at http://www.gc.doe.gov). The proposed 
rule published today does not provide for any Federal mandate likely to 
result in an aggregate expenditure of $100 million or more. Therefore, 
the UMRA does not require a cost benefit analysis of today's proposal.

H. Review Under the Treasury and General Government Appropriations Act, 
1999

    Section 654 of the Treasury and General Government Appropriations 
Act, 1999 (Pub. L. 105-277) requires Federal agencies to issue a Family 
Policymaking Assessment for any rule that may affect family well-being. 
This proposed rule would not have any impact on the autonomy or 
integrity of the family as an institution. Accordingly, DOE has 
concluded that it is not necessary to prepare a Family Policymaking 
Assessment.

I. Review Under Executive Order 12630

    DOE has determined pursuant to Executive Order 12630, 
``Governmental Actions and Interference with Constitutionally Protected 
Property Rights,'' 53 FR 8859 (March 18, 1988) that this proposed rule 
would not result in any takings which might require compensation under 
the Fifth Amendment to the United States Constitution.

J. Review Under the Treasury and General Government Appropriations Act, 
2001

    The Treasury and General Government Appropriations Act, 2001 (44 
U.S.C. 3516, note) provides for agencies to review most disseminations 
of information to the public under guidelines established by each 
agency pursuant to general guidelines issued by OMB. OMB's guidelines 
were published at 67 FR 8452 (February 22, 2002), and DOE's guidelines 
were published at 67 FR 62446 (October 7, 2002). DOE has

[[Page 45519]]

reviewed today's notice under the OMB and DOE guidelines and has 
concluded that it is consistent with applicable policies in those 
guidelines.

K. Review Under Executive Order 13211

    Executive Order 13211, ``Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use,'' 66 FR 28355 
(May 22, 2001) requires Federal agencies to prepare and submit to the 
Office of Information and Regulatory Affairs (OIRA), Office of 
Management and Budget, a Statement of Energy Effects for any proposed 
significant energy action. A ``significant energy action'' is defined 
as any action by an agency that promulgated or is expected to lead to 
promulgation of a final rule, and that: (1) Is a significant regulatory 
action under Executive Order 12866, or any successor order; and (2) is 
likely to have a significant adverse effect on the supply, 
distribution, or use of energy, or (3) is designated by the 
Administrator of OIRA as a significant energy action. For any proposed 
significant energy action, the agency must give a detailed statement of 
any adverse effects on energy supply, distribution, or use should the 
proposal be implemented, and of reasonable alternatives to the action 
and their expected benefits on energy supply, distribution, and use. 
Today's regulatory action is not a significant regulatory action under 
Executive Order 12866. Moreover, it would not have a significant 
adverse effect on the supply, distribution, or use of energy. 
Therefore, it is not a significant energy action, and DOE has not 
prepared a Statement of Energy Effects.

L. Review Under Section 32 of the Federal Energy Administration Act of 
1974

    Under section 301 of the Department of Energy Organization Act 
(Pub. L. 95-91), the Department of Energy must comply with section 32 
of the Federal Energy Administration Act of 1974, as amended by the 
Federal Energy Administration Authorization Act of 1977. (15 U.S.C. 
788) Section 32 provides in part that, where a proposed rule contains 
or involves use of commercial standards, the rulemaking must inform the 
public of the use and background of such standards.
    The rule proposed in this notice incorporates testing methods 
contained in the following commercial standards: (1) IEEE Standard 
C57.12.90-1999, ``IEEE Standard Test Code for Liquid-Immersed 
Distribution, Power and Regulating Transformers and IEEE Guide for 
Short Circuit Testing of Distribution and Power Transformers,'' (2) 
IEEE Standard C57.12.91-2001, ``IEEE Standard Test Code for Dry-Type 
Distribution and Power Transformers,'' (3) IEEE Standard C57.12.00-
2000, ``IEEE Standard General Requirements for Liquid-Immersed 
Distribution, Power and Regulating Transformers,'' (4) IEEE Standard 
C57.12.01-1998, ``IEEE Standard General Requirements for Dry-Type 
Distribution and Power Transformers Including those with Solid Cast 
and/or Resin Encapsulated Windings,'' and (5) NEMA Standards 
Publication No. TP 2-1998, ``Standard Test Method for Measuring the 
Energy Consumption of Distribution Transformers.'' The Department has 
evaluated these standards and is unable to conclude whether they fully 
comply with the requirements of section 32(b) of the Federal Energy 
Administration Act, i.e., they were developed in a manner that fully 
provides for public participation, comment and review.
    As required by section 32(c) of the Federal Energy Administration 
Act, of 1974, as amended, DOE will consult with the Attorney General 
and the Chairman of the Federal Trade Commission, prior to prescribing 
a final rule, concerning the impact on competition of requiring use of 
methods contained in these standards to test distribution transformers.

IV. Public Participation

A. Attendance at Public Meeting

    The time and date of the public meeting are listed in the DATES 
section at the beginning of this notice of proposed rulemaking. The 
public meeting will be held at the U.S. Department of Energy, Forrestal 
Building, Room 1E-245, 1000 Independence Avenue, SW., Washington, DC, 
20585. To attend the public meeting, please notify Ms. Brenda Edwards-
Jones at (202) 586-2945. Foreign nationals visiting DOE Headquarters 
are subject to advance security screening procedures, requiring a 30-
day advance notice. Any foreign national wishing to participate in the 
meeting should advise DOE of this fact as soon as possible by 
contacting Ms. Brenda Edwards-Jones to initiate the necessary 
procedures.

B. Procedure for Submitting Requests To Speak

    Any person who has an interest in today's notice, or who is a 
representative of a group or class of persons that has an interest in 
these issues, may request an opportunity to make an oral presentation. 
Such persons may hand-deliver requests to speak, along with a computer 
diskette or CD in WordPerfect, Microsoft Word, PDF, or text (ASCII) 
file format to the address shown in the ADDRESSES section at the 
beginning of this supplemental notice of proposed rulemaking between 
the hours of 9 a.m. and 4 p.m., Monday through Friday, except Federal 
holidays. Requests may also be sent by mail or e-mail to: 
[email protected].
    Persons requesting to speak should briefly describe the nature of 
their interest in this rulemaking and provide a telephone number for 
contact. The Department requests persons selected to be heard to submit 
an advance copy of their statements at least two weeks before the 
public meeting. At its discretion, DOE may permit any person who cannot 
supply an advance copy of their statement to participate, if that 
person has made advance alternative arrangements with the Building 
Technologies Program. The request to give an oral presentation should 
ask for such alternative arrangements.

C. Conduct of Public Meeting

    The Department will designate a DOE official to preside at the 
public meeting and may also use a professional facilitator to aid 
discussion. The meeting will not be a judicial or evidentiary-type 
public hearing, but DOE will conduct it in accordance with 5 U.S.C. 553 
and section 336 of EPCA. A court reporter will be present to record the 
proceedings and prepare a transcript. The Department reserves the right 
to schedule the order of presentations and to establish the procedures 
governing the conduct of the public meeting. After the public meeting, 
interested parties may submit further comments on the proceedings as 
well as on any aspect of the rulemaking until the end of the comment 
period.
    The public meeting will be conducted in an informal, conference 
style. The Department will present summaries of comments received 
before the public meeting, allow time for presentations by 
participants, and encourage all interested parties to share their views 
on issues affecting this rulemaking. Each participant will be allowed 
to make a prepared general statement (within time limits determined by 
DOE), before the discussion of specific topics. The Department will 
permit other participants to comment briefly on any general statements.
    At the end of all prepared statements on a topic, DOE will permit 
participants to clarify their statements briefly and comment on 
statements made by others. Participants should be prepared to answer 
questions by DOE and by other

[[Page 45520]]

participants concerning these issues. Department representatives may 
also ask questions of participants concerning other matters relevant to 
this rulemaking. The official conducting the public meeting will accept 
additional comments or questions from those attending, as time permits. 
The presiding official will announce any further procedural rules or 
modification of the above procedures that may be needed for the proper 
conduct of the public meeting.
    The Department will make the entire record of this proposed 
rulemaking, including the transcript from the public meeting, available 
for inspection at the U.S. Department of Energy, Forrestal Building, 
Room 1J-018 (Resource Room of the Building Technologies Program), 1000 
Independence Avenue, SW., Washington, DC 20585, (202) 586-9127, between 
9 a.m. and 4 p.m., Monday through Friday, except Federal holidays. Any 
person may buy a copy of the transcript of the public hearing 
proceedings from the transcribing reporter.

D. Submission of Comments

    The Department will accept comments, data, and information 
regarding the proposed rule before or after the public meeting, but no 
later than the date provided at the beginning of this notice of 
proposed rulemaking. Please submit comments, data, and information 
electronically. Send them to the following e-mail address: 
[email protected]. Submit electronic comments in 
WordPerfect, Microsoft Word, PDF, or text (ASCII) file format and avoid 
the use of special characters or any form of encryption. Comments in 
electronic format should be identified by the docket number EE-TP-98-
550 and/or RIN number, and wherever possible carry the electronic 
signature of the author. Absent an electronic signature, comments 
submitted electronically must be followed and authenticated by 
submitting the signed original paper document. No telefacsimiles 
(faxes) will be accepted.
    According to 10 CFR 1004.11, any person submitting information that 
he or she believes to be confidential and exempt by law from public 
disclosure should submit two copies: one copy of the document including 
all the information believed to be confidential, and one copy of the 
document with the information believed to be confidential deleted. The 
Department of Energy will make its own determination about the 
confidential status of the information and treat it according to its 
determination.
    Factors of interest to the Department when evaluating requests to 
treat submitted information as confidential include: (1) A description 
of the items; (2) whether and why such items are customarily treated as 
confidential within the industry; (3) whether the information is 
generally known by or available from other sources; (4) whether the 
information has previously been made available to others without 
obligation concerning its confidentiality; (5) an explanation of the 
competitive injury to the submitting person which would result from 
public disclosure; (6) when such information might lose its 
confidential character due to the passage of time; and (7) why 
disclosure of the information would be contrary to the public interest.

List of Subjects in 10 CFR Part 432

    Administrative practice and procedure, Energy conservation, 
Distribution transformers.

    The Secretary of Energy has approved publication of today's rule.

    Issued in Washington, DC on May 26, 2004.
David K. Garman,
Assistant Secretary, Energy Efficiency and Renewable Energy.
    For the reasons set forth in the preamble, Chapter II of Title 10, 
Code of Federal Regulations, is proposed to be amended by adding a new 
Part 432 to read as set forth below.

PART 432--ENERGY CONSERVATION PROGRAM FOR DISTRIBUTION TRANSFORMERS

Subpart A--General Provisions
Sec.
432.1 Purpose and scope.
432.2 Definitions.
Subpart B--Distribution Transformers
432.10 Definitions.
432.11 Test procedures for measuring energy consumption of 
distribution transformers.
432.12 Manufacturer's determination of efficiency for distribution 
transformers.
432.13 Enforcement testing for distribution transformers.
Appendix A to Subpart B of Part 432--Uniform Test Method for 
Measuring the Energy Consumption of Distribution Transformers
Appendix B to Subpart B of Part 432--Sampling Plan for Enforcement 
Testing
Subpart C--[Reserved]
Subpart D--[Reserved]

    Authority: 42 U.S.C. 6317.

Subpart A--General Provisions


Sec.  432.1  Purpose and scope.

    This part contains energy conservation requirements that the 
Department has promulgated pursuant to section 346 of EPCA, 42 U.S.C. 
6317.


Sec.  432.2  Definitions.

    The following definitions apply for purposes of this part:
    Act means the Energy Policy and Conservation Act of 1975, as 
amended, 42 U.S.C. 6291-6317.
    DOE or the Department means the Department of Energy.
    EPCA means the Energy Policy and Conservation Act of 1975, as 
amended, 42 U.S.C. 6291-6317.
    Secretary means the Secretary of the Department of Energy.

Subpart B--Distribution Transformers


Sec.  432.10  Definitions.

    The following definitions apply for purposes of this subpart:
    Autotransformer means a transformer that:
    (1) Has one physical winding that consists of a series winding part 
and a common winding part;
    (2) Has no isolation between its primary and secondary circuits; 
and
    (3) During step-down operation, has a primary voltage that is equal 
to the total of the series and common winding voltages, and a secondary 
voltage that is equal to the common winding voltage.
    Basic model means a group of distribution transformers manufactured 
by a single manufacturer, that have the same insulation type (i.e., 
liquid-immersed or dry-type), have the same number of phases (i.e., 
single or three), have the same standard kVA rating, and do not have 
any differentiating electrical, physical or functional features that 
affect energy consumption.
    Distribution transformer means a transformer with a primary voltage 
of equal to or less than 35 kV, a secondary voltage equal to or less 
than 600 V, a frequency of 55-65 Hz, and a capacity of 10 kVA to 2500 
kVA for liquid-immersed units and 15 kVA to 2500 kVA for dry-type 
units, and does not include the following types of transformers:
    (1) Autotransformer;
    (2) Drive (isolation) transformer;
    (3) Grounding transformer;
    (4) Harmonic mitigating transformer;
    (5) K-Factor Transformer;
    (6) Machine-Tool (Control) Transformer;
    (7) Non-ventilated Transformer;
    (8) Rectifier Transformer;
    (9) Regulating Transformer;

[[Page 45521]]

    (10) Sealed Transformer;
    (11) Special-Impedance Transformer;
    (12) Testing Transformer;
    (13) Transformer with Tap Range greater than 15 percent;
    (14) Uninterruptible Power Supply Transformer; or
    (15) Welding Transformer.
    Drive (isolation) transformer means a transformer that:
    (1) Isolates an electric motor from the line;
    (2) Accommodates the added loads of drive-created harmonics; and
    (3) Is designed to withstand the additional mechanical stresses 
resulting from an alternating current adjustable frequency motor drive 
or a direct current motor drive.
    Dry-type distribution transformer means a distribution transformer 
in which the core and coil assembly is immersed in a gaseous or dry-
compound insulating medium.
    Efficiency means the ratio of the useful power output to the total 
power input.
    Excitation current or no-load current means the current that flows 
in any winding used to excite the transformer when all other windings 
are open-circuited.
    Grounding transformer means a three-phase transformer intended 
primarily to provide a neutral point for system-grounding purposes, 
either by means of:
    (1) A grounded wye primary winding and a delta secondary winding; 
or
    (2) An autotransformer with a zig-zag winding arrangement.
    Harmonic mitigating transformer means a transformer designed to 
cancel or reduce the harmonics drawn by computer equipment and other 
non-linear power electronic loads.
    K-Factor transformer means a transformer with a K-Factor of 13 or 
greater that is designed to tolerate the additional eddy-current losses 
resulting from harmonics drawn by non-linear loads, usually when the 
ratio of the non-linear load to the linear load is greater than 50 
percent.
    Liquid-immersed distribution transformer means a distribution 
transformer in which the core and coil assembly is immersed in an 
insulating liquid.
    Load loss means, for a distribution transformer, those losses 
incident to a specified load carried by the transformer, including 
losses in the windings as well as stray losses in the conducting parts 
of the transformer. It does not include no-load losses.
    Low-voltage distribution transformer means a dry-type distribution 
transformer with a rated primary voltage of 600 V or less.
    Machine-tool (control) transformer means a transformer that is 
equipped with a fuse or other over current protection device, and is 
generally used for the operation of a solenoid, contactor, relay, 
portable tool, or localized lighting.
    Medium-voltage distribution transformer means a dry-type 
distribution transformer with rated primary voltage between 601 V and 
35 kV.
    No-load loss means those losses that are incident to the excitation 
of the transformer.
    Non-ventilated transformer means a transformer constructed so as to 
prevent external air circulation through the coils of the transformer 
while operating at zero gauge pressure.
    Phase angle means the angle between two phasors, where the two 
phasors represent progressions of periodic waves of either:
    (1) Two voltages;
    (2) Two currents; or
    (3) A voltage and a current of an alternating current circuit.
    Phase angle correction means the adjustment (correction) of 
measurement data to negate the effects of phase angle error.
    Phase angle error means incorrect displacement of the phase angle, 
introduced by the components of the test equipment.
    Rectifier transformer means a transformer that operates at the 
fundamental frequency of an alternating-current system and that is 
designed to have one or more output windings connected to a rectifier.
    Reference temperature means 20 [deg]C for no-load loss, 55 [deg]C 
for liquid-immersed distribution transformers at 50% load, and 75 
[deg]C for both low-voltage and medium-voltage dry-type distribution 
transformers, at 35% load and 50% load, respectively. It is the 
temperature at which the transformer losses must be determined, and to 
which such losses must be corrected if testing is done at a different 
point. (These temperatures are specified in the test method in Appendix 
A to this part.)
    Regulating Transformer means a transformer that varies the voltage, 
the phase angle, or both voltage and phase angle, of an output circuit 
and compensates for fluctuation of load and input voltage, phase angle 
or both voltage and phase angle.
    Sealed Transformer means a transformer designed to remain 
hermetically sealed under specified conditions of temperature and 
pressure.
    Special-Impedance Transformer means any transformer built to 
operate at an impedance outside of the normal impedance range for that 
transformer's kVA rating. The normal impedance range for each kVA 
rating for liquid-immersed and dry-type transformers is shown in Tables 
1 and 2, respectively.

                       Table 1.--Normal Impedance Ranges for Liquid-Immersed Transformers
----------------------------------------------------------------------------------------------------------------
                Single-phase transformers                                Three-phase transformers
----------------------------------------------------------------------------------------------------------------
            kVA                     Impedance (%)                     kVA                    Impedance (%)
----------------------------------------------------------------------------------------------------------------
                   10                      1.0-4.5                           15                     1.0-4.5
                   15                      1.0-4.5                           30                     1.0-4.5
                   25                      1.0-4.5                           45                     1.0-4.5
                 37.5                      1.0-4.5                           75                     1.0-5.0
                   50                      1.5-4.5                        112.5                     1.2-6.0
                   75                      1.5-4.5                          150                     1.2-6.0
                  100                      1.5-4.5                          225                     1.2-6.0
                  167                      1.5-4.5                          300                     1.2-6.0
                  250                      1.5-6.0                          500                     1.5-7.0
                  333                      1.5-6.0                          750                     5.0-7.5
                  500                      1.5-7.0                         1000                     5.0-7.5
                  667                      5.0-7.5                         1500                     5.0-7.5
                  833                      5.0-7.5                         2000                     5.0-7.5
                                                                           2500                     5.0-7.5
----------------------------------------------------------------------------------------------------------------


[[Page 45522]]


                           Table 2.--Normal Impedance Ranges for Dry-Type Transformers
----------------------------------------------------------------------------------------------------------------
                Single-phase transformers                                Three-phase transformers
----------------------------------------------------------------------------------------------------------------
            kVA                     Impedance (%)                     kVA                    Impedance (%)
----------------------------------------------------------------------------------------------------------------
                   15                      1.5-6.0                           15                     1.5-6.0
                   25                      1.5-6.0                           30                     1.5-6.0
                 37.5                      1.5-6.0                           45                     1.5-6.0
                   50                      1.5-6.0                           75                     1.5-6.0
                   75                      2.0-7.0                        112.5                     1.5-6.0
                  100                      2.0-7.0                          150                     1.5-6.0
                  167                      2.5-8.0                          225                     3.0-7.0
                  250                      3.5-8.0                          300                     3.0-7.0
                  333                      3.5-8.0                          500                     4.5-8.0
                  500                      3.5-8.0                          750                     5.0-8.0
                  667                      5.0-8.0                         1000                     5.0-8.0
                  833                      5.0-8.0                         1500                     5.0-8.0
                                                                           2000                     5.0-8.0
                                                                           2500                     5.0-8.0
----------------------------------------------------------------------------------------------------------------

    Temperature Correction means the mathematical correction(s) of 
measurement data, obtained when a transformer is tested at a 
temperature that is different from the reference temperature, to the 
value(s) that would have been obtained if the transformer had been 
tested at the reference temperature.
    Test Current means the current of the electrical power supplied to 
the transformer under test.
    Test Frequency means the frequency of the electrical power supplied 
to the transformer under test.
    Test Voltage means the voltage of the electrical power supplied to 
the transformer under test.
    Testing Transformer means a transformer used in a circuit to 
produce a specific voltage or current for the purpose of testing 
electrical equipment. This type of transformer is also commonly known 
as an Instrument Transformer.
    Total Loss means the sum of the no-load loss and the load loss for 
a transformer.
    Transformer means a static electric device consisting of a winding 
or two or more coupled windings, with a magnetic core, for introducing 
mutual coupling between electric circuits.
    Transformer with Tap Range greater than 15 percent means a 
transformer with a tap range in the primary winding greater than the 
range accomplished with six, 2.5-percent taps, 3 above and 3 below the 
rated primary voltage (e.g., 6 times 2.5 percent = 15 percent).
    Uninterruptible Power Supply Transformer means a transformer that 
supplies power to an uninterruptible power system, which in turn 
supplies power to loads that are sensitive to power failure, power 
sags, over voltage, switching transients, line noise, and other power 
quality factors.
    Waveform Correction means the adjustment(s) (mathematical 
correction(s)) of measurement data obtained with a test voltage that is 
non-sinusoidal, to a value(s) that would have been obtained with a 
sinusoidal voltage.
    Welding Transformer means a transformer designed for use in arc 
welding equipment or resistance welding equipment.


Sec.  432.11  Test procedures for measuring energy consumption of 
distribution transformers.

    The test procedures for measuring the energy efficiency of 
distribution transformers for purposes of EPCA are specified in 
Appendix A to this subpart (``Appendix A'').


Sec.  432.12  Manufacturer's determination of efficiency for 
distribution transformers.

    When a manufacturer or other party (both of which this section 
refers to as a ``manufacturer'') determines the efficiency of a 
distribution transformer in order to comply with an obligation imposed 
on it by or pursuant to Part C of Title III of EPCA, 42 U.S.C. 6311-
6317, this section applies. This section does not apply to enforcement 
testing conducted pursuant to Sec.  432.13 of this part.
    (a) Methods used to determine efficiency.
    (1) General Requirements. A manufacturer must determine the 
efficiency of each basic model of distribution transformer either by 
testing in accordance with Sec.  432.11 of this part and paragraph 
(b)(2) of this section, or by application of an alternative efficiency 
determination method (AEDM) that meets the requirements of paragraphs 
(a)(2) and (a)(3) of this section; provided, however, that a 
manufacturer may use an AEDM to determine the efficiency of one or more 
of its untested basic models only if it determines the efficiency of at 
least five of its other basic models (selected in accordance with 
paragraph (b)(1) of this section) through actual testing.
    (2) Alternative efficiency determination method. A manufacturer may 
apply an AEDM to a basic model only if:
    (i) The AEDM has been derived from a mathematical model that 
represents the electrical characteristics of that basic model;
    (ii) The AEDM is based on engineering and statistical analysis, 
computer simulation or modeling, or other analytic evaluation of 
performance data; and
    (iii) In applying the AEDM to distribution transformers, the 
manufacturer uses the AEDM only for one or more of its basic models in 
one of the following groups of distribution transformers: low-voltage 
dry-type transformers, medium-voltage dry-type transformers, and 
liquid-immersed transformers.
    (3) Substantiation of an alternative efficiency determination 
method. Before using an AEDM, the manufacturer must substantiate the 
AEDM's accuracy and reliability as follows:
    (i) Apply the AEDM to at least five of the manufacturer's basic 
models that have been selected for testing in accordance with paragraph 
(b)(1) of this section, and calculate the power loss for each of these 
basic models;
    (ii) Test at least five units of each of these basic models in 
accordance with the applicable test procedure and paragraph (b)(2) of 
this section, and determine the power loss for each of these basic 
models;
    (iii) The predicted total power loss for each of these basic 
models, calculated by applying the AEDM pursuant to paragraph (a)(3)(i) 
of this section, must be within plus or minus five percent of

[[Page 45523]]

the mean total power loss determined from the testing of that basic 
model pursuant to paragraph (a)(3)(ii) of this section; and
    (iv) Calculate for each of these basic models the percentage that 
its power loss calculated pursuant to paragraph (a)(3)(i) is of its 
power loss determined from testing pursuant to paragraph (a)(3)(ii), 
compute the average of these percentages, and that calculated average 
power loss, expressed as a percentage of the average power loss 
determined from testing, must be no less than 97 percent and no greater 
than 103 percent.
    (4) Subsequent verification of an AEDM.
    (i) Each manufacturer shall periodically select basic models 
representative of those to which it has applied an AEDM, and for each 
basic model selected shall either:
    (A) Subject a sample of at least five units to testing in 
accordance with the applicable test procedure and paragraph (b)(2) of 
this section by an independent testing laboratory; or
    (B) Have an independent state-registered professional engineer, who 
is qualified to perform an evaluation of distribution transformer 
efficiency in a highly competent manner and who is not an employee of 
the manufacturer, review the manufacturer's representations and certify 
that the results of the AEDM accurately represent the total power loss 
and efficiency of the basic model.
    (ii) Each manufacturer that has used an AEDM under this section 
shall have available for inspection by the Department of Energy records 
showing: the method or methods used; the mathematical model, the 
engineering or statistical analysis, computer simulation or modeling, 
and other analytic evaluation of performance data on which the AEDM is 
based; complete test data, product information, and related information 
that the manufacturer has generated or acquired pursuant to paragraphs 
(a)(3) and (a)(4)(i) of this section; and the calculations used to 
determine the efficiency and total power losses of each basic model to 
which the AEDM was applied.
    (iii) If requested by the Department, the manufacturer shall 
conduct simulations to predict the performance of particular basic 
models of distribution transformers specified by the Department, 
analyses of previous simulations conducted by the manufacturer, sample 
testing of basic models selected by the Department, or a combination of 
the foregoing.
    (b) Additional testing requirements.
    (1) Selection of basic models for testing if an AEDM is to be 
applied.
    (i) A manufacturer must select basic models for testing in 
accordance with the following criteria:
    (A) Two of the basic models must be among the five basic models 
with the highest unit volumes of production by the manufacturer in the 
prior year, or during the prior 12-calendar-month period beginning in 
2003,\1\ whichever is later;
---------------------------------------------------------------------------

    \1\ When identifying these five basic models, any basic model 
that does not comply with Federal energy conservation standards for 
distribution transformers that may be in effect shall be excluded 
from consideration.
---------------------------------------------------------------------------

    (B) No two basic models should have the same combination of power 
and voltage ratings; and
    (C) At least one basic model should be single-phase and at least 
one should be three-phase.
    (ii) In any instance where it is impossible for a manufacturer to 
select basic models for testing in accordance with all of these 
criteria, the criteria shall be given priority in the order in which 
they are listed. Within the limits imposed by the criteria, basic 
models shall be selected randomly.
    (2) Selection of units for testing within a basic model. For each 
basic model a manufacturer selects for testing, it shall select a 
sample of units at random and test them. The sample shall be comprised 
of production units of the basic model, or units that are 
representative of such production units. The sample size shall be not 
fewer than five units, except that when the manufacturer would produce 
fewer than five units of a basic model over a reasonable period of time 
(approximately 180 days), then it must test each unit. However, a 
manufacturer may not use a basic model with a sample size of fewer than 
five units to substantiate or verify an AEDM pursuant to paragraphs 
(a)(3) or (a)(4) of this section. In a test of compliance with a 
represented efficiency:
    The average efficiency of the sample, X, which is defined by
    [GRAPHIC] [TIFF OMITTED] TP29JY04.000
    

where Xi is the measured efficiency of unit i and n is the 
number of units tested, must satisfy the condition:
[GRAPHIC] [TIFF OMITTED] TP29JY04.001


where RE is the represented efficiency.


Sec.  432.13  Enforcement testing for distribution transformers.

    (a) Test notice. Upon receiving information in writing, concerning 
the energy performance of a particular distribution transformer sold by 
a particular manufacturer or private labeler, which indicates that the 
transformer may not be in compliance with the applicable energy 
efficiency standard, or upon undertaking to ascertain the accuracy of 
the efficiency rating on the nameplate or in marketing materials for a 
distribution transformer, disclosed pursuant to this part, the 
Department may conduct testing of that equipment under this subpart by 
means of a test notice addressed to the manufacturer in accordance with 
the following requirements:
    (1) The test notice procedure will only be followed after the 
Department has examined the underlying test data (or, where 
appropriate, data as to use of an AEDM) provided by the manufacturer 
and after the manufacturer has been offered the opportunity to meet 
with the Department to verify, as applicable, compliance with the 
applicable efficiency standard, or the accuracy of labeling 
information, or both. In addition, where compliance of a basic model 
was certified based on an AEDM, the Department shall have the 
discretion to pursue the provisions of Sec.  432.12(a)(4)(iii) prior to 
invoking the test notice procedure. The Department shall be permitted 
to observe any reverification procedures undertaken pursuant to this 
subpart, and to inspect the results of such reverification.
    (2) The Department will mail or deliver the test notice to the 
plant manager or other responsible official, as designated by the 
manufacturer.
    (3) The test notice will specify the basic model to be selected for 
testing, the method of selecting the test sample, the date and time at 
which testing shall be initiated, the date by which testing is 
scheduled to be completed and the facility at which testing will be 
conducted. The test notice may also provide for situations in which the 
specified basic model is unavailable for testing, and may include 
alternative basic models. The specified basic model may be one either 
that the manufacturer has rated by actual testing or that it has rated 
by the use of an AEDM.
    (4) The Department may require in the test notice that the 
manufacturer shall ship at his expense a reasonable number of units of 
a basic model specified in such test notice to a testing laboratory 
designated by the Department. The number of units of a basic model 
specified in a test notice shall not exceed twenty (20).

[[Page 45524]]

    (5) Except as required or provided in paragraphs (a)(6) or (a)(7) 
of this section, initially the Department will test five units.
    (6) Except as provided in paragraph (a)(7) of this section, if 
fewer than five units of a basic model are available for testing when 
the manufacturer receives the test notice, then
    (i) DOE will test the available unit(s); or
    (ii) If one or more other units of the basic model are expected to 
become available within six months, DOE may instead, at its discretion, 
test either:
    (A) The available unit(s) and one or more of the other units that 
subsequently become available (up to a maximum of twenty); or
    (B) Up to twenty of the other units that subsequently become 
available.
    (7) Notwithstanding paragraphs (a)(5) and (a)(6) of this section, 
if testing of the available or subsequently available units of a basic 
model would be impractical, as for example where a basic model is very 
large, has unusual testing requirements, or has limited production, the 
Department may in its discretion decide to base the determination of 
compliance on the testing of fewer than the available number of units, 
if the manufacturer so requests and demonstrates that the criteria of 
this paragraph are met.
    (8) When testing units under paragraphs (a)(5), (a)(6), or (a)(7) 
of this section, DOE shall perform the following number of tests:
    (i) If DOE tests four or more units, it will test each unit once;
    (ii) If DOE tests two or three units, it will test each unit twice; 
or
    (iii) If DOE tests one unit, it will test that unit four times.
    (9) Within five working days of the time the units are selected, 
the manufacturer shall ship the specified test units of the basic model 
to the testing laboratory.
    (b) Testing laboratory. Whenever the Department conducts 
enforcement testing at a designated laboratory in accordance with a 
test notice under this section, the resulting test data shall 
constitute official test data for that basic model. Such test data will 
be used by the Department to make a determination of compliance or 
noncompliance.
    (c) Sampling. The determination that a manufacturer's basic model 
complies with its labeled efficiency, or the applicable energy 
efficiency standard, shall be based on the testing conducted in 
accordance with the statistical sampling procedures set forth in 
Appendix B of this subpart and the test procedures specified for 
distribution transformers.
    (d) Test unit selection. The Department shall select a batch, a 
batch sample, and test units from the batch sample in accordance with 
the following provisions of this paragraph and the conditions specified 
in the test notice.
    (1) The batch may be subdivided by the Department utilizing 
criteria specified in the test notice.
    (2) The Department will then randomly select a batch sample of up 
to 20 units from one or more subdivided groups within the batch. The 
manufacturer shall keep on hand all units in the batch sample until 
such time as the basic model is determined to be in compliance or non-
compliance.
    (3) The Department will randomly select individual test units 
comprising the test sample from the batch sample.
    (4) All random selection shall be achieved by sequentially 
numbering all of the units in a batch sample and then using a table of 
random numbers to select the units to be tested.
    (e) Test unit preparation.
    (1) Prior to and during the testing, a test unit selected in 
accordance with paragraph (d) of this section shall not be prepared, 
modified, or adjusted in any manner unless such preparation, 
modification, or adjustment is allowed by the applicable Department of 
Energy test procedure.
    (2) No quality control, testing, or assembly procedures shall be 
performed on a test unit, or any parts and sub-assemblies thereof, that 
is not performed during the production and assembly of all other units 
included in the basic model.
    (3) A test unit shall be considered defective if such unit is 
inoperative or is found to be in noncompliance due to failure of the 
unit to operate according to the manufacturer's design and operating 
instructions. Defective units, including those damaged due to shipping 
or handling, shall be reported immediately to the Department. The 
Department shall authorize testing of an additional unit on a case-by-
case basis.
    (f) Testing at manufacturer's option.
    (1) If a manufacturer's basic model is determined to be in 
noncompliance with the applicable energy performance standard at the 
conclusion of Department testing in accordance with the sampling plan 
specified in Appendix B of this subpart, the manufacturer may request 
that the Department conduct additional testing of the basic model 
according to procedures set forth in Appendix B of this subpart and the 
test procedures specified for distribution transformers.
    (2) All units tested under this paragraph shall be selected and 
tested in accordance with the provisions given in paragraphs (a)(9), 
(b), (d) and (e) of this section.
    (3) The manufacturer shall bear the cost of all testing conducted 
under this paragraph.
    (4) The manufacturer shall cease distribution of the basic model 
tested under the provisions of this paragraph from the time the 
manufacturer elects to exercise the option provided in this paragraph 
until the basic model is determined to be in compliance. The Department 
may seek civil penalties for all units distributed during such period.
    (5) If the additional testing results in a determination of 
compliance, a notice of allowance to resume distribution shall be 
issued by the Department.

Appendix A to Subpart B of Part 432--Uniform Test Method for Measuring 
the Energy Consumption of Distribution Transformers

1.0 Definitions

    The definitions contained in Sec. Sec.  432.2 and 432.10 are 
applicable to this Appendix A.

2.0 Accuracy Requirements

    Equipment and methods for loss measurement shall be sufficiently 
accurate that measurement error will be limited to the values shown 
in Table 2.1.

 Table 2.1--Test System Accuracy Requirements for Each Measured Quantity
------------------------------------------------------------------------
                                                            Test system
                    Measured quantity                        accuracy
------------------------------------------------------------------------
Power Losses............................................    
                                                                   3.0 %
Voltage.................................................    
                                                                   0.5 %
Current.................................................    
                                                                   0.5 %
Resistance..............................................    
                                                                   0.5 %
Temperature.............................................    
                                                              1.0 [deg]C
------------------------------------------------------------------------

    Only instrument transformers meeting the 0.3 metering accuracy 
class, or better, may be used under this test method.

3.0 Resistance Measurements

3.1 General Considerations

    Measure or establish the winding temperature at the time of the 
winding resistance measurement.
    Measure the direct current resistance (Rdc) of 
transformer windings by one of the methods outlined in section 3.3. 
The methods of section 3.5 must be used to correct load losses to 
the applicable reference temperature from the temperature at which 
they are measured. Observe precautions while taking measurements, 
such as those in section 3.4, in order to maintain measurement 
uncertainty limits specified in Table 2.1.

3.2 Temperature Determination of Windings and Pre-conditions for 
Resistance Measurement

    Make temperature measurements in protected areas where the air 
temperature is

[[Page 45525]]

stable and there are no drafts. Determine the winding temperature 
(Tdc) for liquid-immersed and dry-type distribution 
transformers by the methods described in sections 3.2.1 and 3.2.2, 
respectively.

3.2.1 Liquid-Immersed Distribution Transformers

    Record the winding temperature (Tdc) of liquid-
immersed transformers as the average of top and bottom thermocouples 
or other temperature sensing devices applied to the outside of the 
transformer tank. The top sensor should be located at the level of 
the oil and the bottom sensor should be near the tank bottom or at 
the lower radiator header if applicable.
    Make this determination under either of the following 
conditions:
    (a) The windings have been under insulating liquid with no 
excitation and no current in the windings for four hours before the 
dc resistance is measured; or
    (b) The temperature of the insulating liquid has stabilized, and 
the difference between the top and bottom temperature does not 
exceed 5 [deg]C.

3.2.2 Dry-Type Distribution Transformers

    Record the winding temperature (Tdc) of ventilated 
dry-type transformers as the average of readings of four or more 
thermometers, thermocouples, or other suitable temperature sensors 
inserted within the coils. Sensing points of the measuring devices 
must be placed as close as possible to the winding conductors.
    For sealed units such as epoxy-coated or epoxy-encapsulated 
distribution transformers, the temperature of the windings must be 
recorded as either:
    (1) The average of four or more temperature sensors located on 
the enclosure and cover as close to different parts of the winding 
assemblies as possible; or
    (2) After allowing a stabilizing interval with no excitation and 
no current in the windings for at least 24 hours, the ambient 
temperature of the test area.
    The following conditions must be met immediately before taking 
cold-resistance measurements:
    (a) All internal temperatures measured by the internal 
temperature sensors must not differ from the test area ambient 
temperature by more than 2 [deg]C.
    (b) Enclosure surface temperatures for sealed units must not 
differ from the test area ambient temperature by more than 2 [deg]C.
    (c) Test area ambient temperature should not have changed by 
more than 3 [deg]C for 3 hours before the test.
    (d) Neither voltage nor current has been applied to the unit 
under test for 24 hours. In addition, the period since application 
of voltage or current must exceed 24 hours by any added amount of 
time necessary for the temperature of the transformer windings to 
stabilize at the level of the ambient temperature. However, this 
added amount of time need not exceed 24 hours.

3.3 Resistance Measurement Methods

    Make resistance measurements using either the resistance bridge 
method, the voltmeter-ammeter method or a resistance meter. In each 
instance when this Uniform Test Method is used to test more than one 
unit of a basic model to determine the efficiency of that basic 
model, the resistance of the units being tested may be determined 
from making resistance measurements on only one of the units.

3.3.1 Resistance Bridge Methods

    If the resistance bridge method is selected, use either the 
Wheatstone or Kelvin bridge circuit (or the equivalent of either).

3.3.1.1 Wheatstone Bridge

    This bridge is best suited for measuring resistances larger than 
ten ohms. A schematic diagram of a Wheatstone bridge with a 
representative transformer under test is shown in Figure 3.1.
[GRAPHIC] [TIFF OMITTED] TP29JY04.002

Where:

Rdc is the resistance of the transformer winding being 
measured,
Rs is a standard resistor having the resistance 
Rs,
Ra, Rb are two precision resistors with 
resistance values Ra and Rb, respectively; at 
least one resistor must have a provision for resistance adjustment,
Rt is a resistor for reducing the time constant of the 
circuit,
D is a null detector, which may be either a micro ammeter or 
microvoltmeter or equivalent instrument for observing that no signal 
is present when the bridge is balanced, and
Vdc is a source of dc voltage for supplying the power to 
the Wheatstone Bridge.

    In the measurement process, turn on the source (Vdc), 
and adjust the resistance ratio (Ra/Rb) to 
produce zero signal at the detector (D). Determine the winding 
resistance by using equation 3-1 as follows:

Rdc = Rs (Ra/Rb) (3-1)

3.3.1.2 Kelvin Bridge

    This bridge separates the resistance of the connecting 
conductors to the transformer winding being measured from the 
resistance of the winding, and therefore is best suited for 
measuring resistances of ten ohms and smaller. A schematic diagram 
of a Kelvin bridge with a representative transformer under test is 
shown in Figure 3.2.

[[Page 45526]]

[GRAPHIC] [TIFF OMITTED] TP29JY04.003

    The Kelvin Bridge has seven of the same type of components as in 
the Wheatstone Bridge. It has two more resistors than the Wheatstone 
bridge, Ra1 and Rb1. At least one of these 
resistors must have adjustable resistance. In the measurement 
process, the source is turned on, two resistance ratios 
(Ra/Rb) and (Ra1/Rb1) 
are adjusted to be equal, and then the two ratios are adjusted 
together to balance the bridge producing zero signal at the 
detector. Determine the winding resistance by using equation 3-2 as 
follows:

Rdc = Rs (Ra/Rb) (3-2),

as with the Wheatstone bridge, with an additional condition that:

(Ra/Rb) = (Ra1/Rb1) (3-
3)

    The Kelvin bridge provides two sets of leads, current-carrying 
and voltage-sensing, to the transformer terminals and the standard 
resistor, thus eliminating voltage drops from the measurement in the 
current-carrying leads as represented by Rd.

3.3.2 Voltmeter-Ammeter Method

    Employ the voltmeter-ammeter method only if the rated current of 
the winding is greater than one ampere and the test current is 
limited to 15% of the winding current. Connect the transformer 
winding under test to the circuit shown in Figure 3.3.
[GRAPHIC] [TIFF OMITTED] TP29JY04.004

Where:

A is an ammeter or a voltmeter-shunt combination for measuring the 
current (Imdc) in the transformer winding,
V is a voltmeter with sensitivity in the millivolt range for 
measuring the voltage (Vmdc) applied to the transformer 
winding,
Rdc is the resistance of the transformer winding being 
measured,
Rt is a resistor for reducing the time constant of the 
circuit, and
Vdc is a source of dc voltage for supplying power to the 
measuring circuit.
    To perform the measurement, turn on the source to produce 
current no larger than 15 percent of the rated current for the 
winding. Wait until the current and voltage readings have stabilized 
and then take simultaneous readings of voltage and current. 
Determine the winding resistance Rdc by using equation 3-
4 as follows:

Rdc = (Vmdc/Imdc) (3-4)

Where:

Vmdc is the voltage measured by the voltmeter V, and

[[Page 45527]]

Imdc is the current measured by the ammeter A.
    As shown in Figure 3.3, separate current and voltage leads must 
be brought to the transformer terminals. (This eliminates the errors 
due to lead and contact resistance.)

3.3.3 Resistance Meters

    Resistance meters may be based on voltmeter-ammeter, or 
resistance bridge, or some other operating principle. A particular 
meter may be used to measure a transformer's winding resistance only 
if the meter's specifications for resistance range, current range, 
and ability to measure highly inductive resistors cover the 
characteristics of the transformer being tested. Also the meter's 
specifications for accuracy must meet the applicable criteria of 
Table 2.1 in section 2.0.

3.4 Precautions in Measuring Winding Resistance

3.4.1 Required actions

    The following guidelines must be observed when making resistance 
measurements:
    (a) Use separate current and voltage leads when measuring small 
(< 10 ohms) resistance.
    (b) Use null detectors in bridge circuits, and measuring 
instruments in voltmeter-ammeter circuits, that have sensitivity and 
resolution sufficient to enable observation of at least 0.1 percent 
change in the measured resistance.
    (c) Maintain the dc test current at or below 15 percent of the 
rated winding current.
    (d) Inclusion of a stabilizing resistor Rt (see 
section 3.4.2) will require higher source voltage.
    (e) Disconnect the null detector (if a bridge circuit is used) 
and voltmeter from the circuit before the current is switched off, 
and switch off current by a suitable insulated switch.

3.4.2 Guideline for Time Constant

    The following guideline is suggested for the tester as a means 
to facilitate the measurement of resistance in accordance with the 
accuracy requirements of section 2.0:
    The accurate reading of resistance Rdc may be 
facilitated by shortening the time constant. This is done by 
introducing a resistor Rt in series with the winding 
under test in both the bridge and voltmeter-ammeter circuits as 
shown in Figures 3.1 to 3.3. The relationship for the time constant 
is:

Tc = (Ltc/Rtc) (3-5)

Where:

Tc is the time constant in seconds,
Ltc is the total magnetizing and leakage inductance of 
the winding under test, in henries, and
Rtc is the total resistance in ohms, consisting of 
Rt in series with the winding resistance Rdc.

    Because Rtc is in the denominator of the expression 
for the time constant, increasing the size of resistor 
Rtc will decrease the time constant. If the time constant 
in a given test circuit is too high for the resistance readings to 
be stable, then a higher resistance can be substituted for the 
existing Rtc, and successive replacements can be made 
until adequate stability is reached.

3.5 Conversion of Resistance Measurements

    Resistance measurements must be corrected, from the temperature 
at which the winding resistance measurements were made, to the 
reference temperature. As specified in these test procedures, the 
reference temperature for liquid-immersed transformers loaded at 50 
percent of the rated load is 55 [deg]C. For medium-voltage, dry-type 
transformers loaded at 50 percent of the rated load, and for low-
voltage, dry-type transformers loaded at 35 percent of the rated 
load, the reference temperature is 75[deg]C.
    Correct measurement temperatures to the DOE reference 
temperature using equation 3-6 as follows:

Rts = Rdc [(Ts + Tk)/
(Tdc + Tk)] (3-6)

Where:

Rts is the resistance at the reference temperature, 
Ts,
Rdc is the measured resistance at temperature, 
Tdc,
Ts is the reference temperature in [deg]C,
Tdc is the temperature at which resistance was measured 
in [deg]C, and
Tk is 234.5 [deg]C for copper or 225 [deg]C for aluminum. 
Where copper and aluminum windings are employed in the same 
transformer, use 229 [deg]C.

4.0 Loss Measurement

4.1 General Considerations

    The efficiency of a transformer is computed from the total 
transformer losses, which are determined from the measured value of 
the no-load loss and load loss power components. Each of these two 
power loss components is measured separately using functionally 
identical test sets. The measured quantities will need correction 
for instrumentation losses and may need corrections for known phase 
angle errors in measuring equipment and for the wave form distortion 
in the test voltage. Any power loss not measured at the applicable 
reference temperature must be adjusted to that reference 
temperature. The measured load loss must also be adjusted to a 
specified output loading level if not measured at the specified 
output loading level.

4.2 Measurement of Power Losses

4.2.1 No-Load Loss

    Measure the no-load loss and apply corrections as described in 
section 4.4, using the appropriate test set as described in section 
4.3.

4.2.2 Load Loss

    Measure the load loss and apply corrections as described in 
section 4.5, using the appropriate test set as described in section 
4.3.

4.3 Test Sets

    The same test set may be used for both the no-load loss and load 
loss measurements provided the range of the test set encompasses the 
test requirements of both tests. Calibrate the test set to national 
standards to meet the tolerances in Table 2.1 in section 2.0. In 
addition, the wattmeter, current measuring system and voltage 
measuring system must be calibrated separately if the overall test 
set calibration is outside the tolerance as specified in section 2 
or the individual phase angle error exceeds the values specified in 
section 4.5.3.
    A test set based on the wattmeter-voltmeter-ammeter principle 
may be used to measure the power loss and the applied voltage and 
current of a transformer where the transformer's test current and 
voltage are within the measurement capability of the measuring 
instruments. Current and voltage transformers, known collectively as 
instrument transformers, or other scaling devices such as resistive 
or capacitive dividers for voltage, may be used in the above 
circumstance, and must be used in place of an instrument to measure 
current or voltage where the current or voltage of the transformer 
under test exceeds the measurement capability of such instrument. 
Thus, a test set may include a combination of measuring instruments 
and instrument transformers (or other scaling devices), so long as 
the current or voltage of the transformer under test does not exceed 
the measurement capability of any of the instruments.

4.3.1 Single Phase Test Sets

    Use these for testing single phase distribution transformers.

4.3.1.1 Without Instrument Transformers

    A single-phase test set without an instrument transformer is 
shown in Figure 4.1.

[[Page 45528]]

[GRAPHIC] [TIFF OMITTED] TP29JY04.005

Where:

W is a wattmeter used to measure Pnm and Plm, 
the no-load and load loss power, respectively,
Vrms is a true root-mean-square (rms) voltmeter used to 
measure Vr(nm) and Vlm, the rms test voltages 
in no-load and load loss measurements, respectively,
Vav is an average sensing voltmeter, calibrated to 
indicate rms voltage for sinusoidal waveforms and used to measure 
Va(nm), the average voltage in no-load loss measurements,
A is an rms ammeter used to measure test current, especially 
Ilm, the load loss current, and
(SC) is a conductor for providing a short-circuit across the output 
windings for the load loss measurements.

    Either the primary or the secondary winding can be connected to 
the test set. However, more compatible voltage and current levels 
for the measuring instruments are available if for no-load loss 
measurements the secondary (low voltage) winding is connected to the 
test set, and for load loss measurements the primary winding is 
connected to the test set. Use the average-sensing voltmeter, 
Vav, only in no-load loss measurements.

4.3.1.2 With Instrument Transformers

    A single-phase test set with instrument transformers is shown in 
Figure 4.2. This circuit has the same four measuring instruments as 
that in Figure 4.1. The current and voltage transformers, designated 
as (CT) and (VT), respectively, are added.
[GRAPHIC] [TIFF OMITTED] TP29JY04.006

4.3.2 Three-Phase Test Sets

    Use these for testing three-phase distribution transformers.

4.3.2.1 Without Instrument Transformers

    A three-phase test set without instrument transformers is shown 
in Figure 4.3. This test set is essentially the same circuit shown 
in Figure 4.1 repeated three times, and the instruments are 
individual devices as shown. As an alternative, the entire 
instrumentation system of a three-phase test set without 
transformers may consist of a multi-function analyzer.

[[Page 45529]]

[GRAPHIC] [TIFF OMITTED] TP29JY04.007

    Either group of windings, the primary or the secondary, can be 
connected in wye or delta configuration. If both groups of windings 
are connected in the wye configuration for the no-load test, the 
neutral of the winding connected to the test set must be connected 
to the neutral of the source to provide a return path for the 
neutral current.
    In the no-load loss measurement, the voltage on the winding must 
be measured. Therefore a provision must be made to switch the 
voltmeters for line-to-neutral measurements for wye-connected 
windings and for line-to-line measurements for delta-connected 
windings.

4.3.2.2 With Instrument Transformers

    A three-phase test set with instrument transformers is shown in 
Figure 4.4. This test set is essentially the same circuit shown in 
Figure 4.2 repeated three times. Provision must be made to switch 
the voltmeters for line-to-neutral and line-to-line measurements as 
in section 4.3.2.1. The voltage sensors (``coils'') of the 
wattmeters must always be connected in the line-to-neutral 
configuration.
[GRAPHIC] [TIFF OMITTED] TP29JY04.008


[[Page 45530]]



4.3.3 Test Set Neutrals

    A four-wire, three-wattmeter test circuit must be used in making 
measurements. For delta-wound transformers, a neutral deriving 
transformer must be used to obtain neutral and ground for the test.

4.4 No-Load Losses: Measurement and Calculations

4.4.1 General Considerations

    Make measurement corrections:
    (1) For instrumentation losses;
    (2) When the waveform of the applied voltage is non-sinusoidal; 
and
    (3) When the core temperature or liquid temperature is outside 
the 20 [deg]C  10 [deg]C range.

4.4.2 No-Load Loss Test

    The purpose of the no-load loss test is to measure no-load 
losses at a specified excitation voltage and a specified frequency. 
The no-load loss determination must be based on a sine-wave voltage 
corrected to the reference temperature. Connect either of the 
transformer windings, primary or secondary, to the appropriate test 
set of Figures 4.1 to 4.4, giving consideration to precaution (b) 
below. Leave the unconnected winding(s) open circuited. Apply the 
rated voltage at rated frequency, as measured by the average-sensing 
voltmeter, to the transformer. Take the readings of the wattmeter(s) 
and the average-sensing and true rms voltmeters. Observe the 
precautions (a), (b), and (c) below:
    (a) Voltmeter connections. When correcting to a sine-wave basis 
using the average-voltmeter method, the voltmeter connections must 
be such that the waveform applied to the voltmeters is the same as 
the waveform across the energized windings.
    (b) Energized windings. Either the high voltage or the low 
voltage winding of the transformer under test may be energized. 
Energize not less than 25 percent of the winding.
    (c) Voltage and frequency. The no-load loss test must be 
conducted with rated voltage impressed across the transformer 
terminals using a voltage source at a frequency equal to the rated 
frequency of the transformer under test, unless otherwise specified.
    Adjust the voltage to the specified value as indicated by the 
average-sensing voltmeter. Record the values of rms voltage, rms 
current, electrical power, and average voltage as close to 
simultaneously as possible. For a three-phase transformer, take all 
of the readings on one phase before proceeding to the next, and 
record the average of the three rms voltmeter readings as the rms 
voltage value.

    Note: When the tester uses a power supply that is not 
synchronized with an electric utility grid, such as a dc/ac motor-
generator set, check the frequency and maintain it within 0.5 percent of the rated frequency of the transformer under 
test. A power source that is directly connected to, or synchronized 
with, an electric utility grid need not be monitored for frequency.

4.4.3 Corrections

4.4.3.1 Correction for Instrumentation Losses

    Determine the losses attributable to the voltmeters, ammeter, 
and wattmeter, and to the instrument transformers if they are used, 
and deduct these losses from the measurement of total no-load 
losses.

4.4.3.2 Correction for Non-Sinusoidal Applied Voltage

    The measured value of no-load loss must be corrected to a 
sinusoidal voltage, except when waveform distortion in the test 
voltage causes the magnitude of the correction to be less than 1%. 
In such a case, no correction is required.
    To make a correction where the distortion requires a correction 
of 5% or less, use equation 4-1. If the distortion requires a 
correction to be greater than 5%, improve the test voltage and re-
test. Repeat until the distortion requires a correction of 5% or 
less.
    Determine the no-load losses of the transformer corrected for 
sine-wave basis from the measured value by using equation 4-1 as 
follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.009

Where:

Pncl is the no-load loss corrected to a sine-wave basis 
at the temperature (Tnm) at which no-load loss is 
measured,
Pnm is the measured no-load loss at temperature 
Tnm,
P1 is the per unit hysteresis loss,
P2 is the per unit eddy-current loss,
P1 + P2 = 1,
[GRAPHIC] [TIFF OMITTED] TP29JY04.010

Vr(nm) is the test voltage measured by rms voltmeter, and
Va(nm) is the test voltage measured by average-voltage 
voltmeter.
    The two loss components (P1 and P2) are 
assumed equal in value, each assigned a value of 0.5 per unit, 
unless the actual measurement-based values of hysteresis and eddy-
current losses are available (in per unit form), in which case the 
actual measurements apply.

4.4.3.3 Correction of No-Load Loss to Reference Temperature

    After correcting the measured no-load loss for waveform 
distortion, correct the loss to the reference temperature of 20 
[deg]C. If the no-load loss measurements were made between 10 [deg]C 
and 30 [deg]C, this correction is not required. If the correction to 
reference temperature is applied, then the core temperature of the 
transformer during no-load loss measurement (Tnm) must be 
determined within  10 [deg]C of the true average core 
temperature. Correct the no-load loss to the reference temperature 
by using equation 4-2 as follows:

Pnc=Pncl [(1 + 0.00065 (Tnm - 
Tnr)] (4-2)
Where:

Pnc is the no-load losses corrected for waveform 
distortion and then to the reference temperature of 20[deg]C,
Pncl is the no-load losses, corrected for waveform 
distortion, at temperature Tnm,
Tnm is the core temperature during the measurement of no-
load losses, and
Tnr is the reference temperature, 20 [deg]C.

4.5 Load Losses: Measurement and Calculations

4.5.1 General Considerations

    The load losses of a transformer are those losses incident to a 
specified load carried by the transformer. Load losses consist of 
ohmic loss in the windings due to the load current and stray losses 
due to the eddy currents induced by the leakage flux in the 
windings, core clamps, magnetic shields, tank walls, and other 
conducting parts. The ohmic loss of a transformer varies directly 
with temperature, whereas the stray losses vary inversely with 
temperature.
    For a transformer with a tap changer, the test must be conducted 
at the rated current and voltage of the nominal tap position.

4.5.2 Tests for Measuring Load Losses

    Connect the transformer with either the high-voltage or low-
voltage windings to the appropriate test set. Then short-circuit the 
winding that was not connected to the test set. Apply a voltage at 
the rated frequency (of the transformer under test) to the connected 
windings to produce the rated current in the transformer. Take the 
readings of the wattmeter(s), the ammeters(s), and rms voltmeter(s).
    Regardless of the test set selected, the following preparatory 
requirements must be satisfied for accurate test results:
    (a) Determine the temperature of the windings using the 
applicable method in section 3.2.1 or section 3.2.2.
    (b) The conductors used to short-circuit the windings must have 
a cross-sectional area equal to, or greater than, the corresponding 
transformer leads.
    (c) When the tester uses a power supply that is not synchronized 
with an electric utility grid, such as a dc/ac motor-generator set, 
follow the provisions of the Note in section 4.4.2.

4.5.3 Corrections

4.5.3.1 Correction for Instrumentation Losses

    Determine the losses attributable to the voltmeters, ammeter, 
wattmeter and short-circuiting conductor (SC), and to the instrument 
transformers if they are used, and deduct these losses from the 
measurement of total load losses.

4.5.3.2 Correction for Phase Angle Errors

    Corrections for phase angle errors are not required if the 
instrumentation is calibrated over the entire range of power factors 
and phase angle errors. Otherwise, determine whether to correct for 
phase angle errors from the magnitude of the normalized per unit 
correction, [beta]n, obtained by using equation 4-3 as 
follows:

[[Page 45531]]

[GRAPHIC] [TIFF OMITTED] TP29JY04.011

    The correction must be applied if [beta]n is outside 
the limits of 0.01. If [beta]n is within the 
limits of 0.01, the correction is permitted but not 
required.
    If the correction for phase angle errors is to be applied, first 
examine the total system phase angle ([beta]w-
[beta]v+[beta]c). Where the total system phase 
angle is equal to or less than 12 milliradians (41 minutes), use either equation 4-4 or 4-5 to correct the 
measured load loss power for phase angle errors, and where the total 
system phase angle exceeds 12 milliradians (41 minutes) use equation 4-5, as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.012

[GRAPHIC] [TIFF OMITTED] TP29JY04.013

    The symbols in this section (4.5.3.2) have the following 
meanings:

Plc1 is the corrected wattmeter reading for phase angle 
errors,
Plm is the actual wattmeter reading,
Vlm is the measured voltage at the transformer winding,
Ilm is the measured rms current in the transformer 
winding,
[GRAPHIC] [TIFF OMITTED] TP29JY04.014

[GRAPHIC] [TIFF OMITTED] TP29JY04.015

[beta]w is the phase angle error (in radians) of the 
wattmeter; the error is positive if the phase angle between the 
voltage and current phasors as sensed by the wattmeter is smaller 
than the true phase angle, thus effectively increasing the measured 
power,
[beta]v is the phase angle error (in radians) of the 
voltage transformer; the error is positive if the secondary voltage 
leads the primary voltage, and
[beta]c is the phase angle error (in radians) of the 
current transformer; the error is positive if the secondary current 
leads the primary current.

    The instrumentation phase angle errors used in the correction 
equations must be specific for the test conditions involved.

4.5.3.3 Temperature Correction of Load Loss

    When the measurement of load loss is made at a temperature 
Tlm that is different from the reference temperature, use 
the procedure summarized in the equations 4-6 to 4-10 to correct the 
measured load loss to the reference temperature.
    Calculate the ohmic loss (Pe) by using equation 4-6 
as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.016

    Obtain the stray loss by subtracting the calculated ohmic loss 
from the measured load loss, by using equation 4-7 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.017

    Correct the ohmic and stray losses to the reference temperature 
for the load loss by using equations 4-8 and 4-9, respectively, as 
follows:

[[Page 45532]]

[GRAPHIC] [TIFF OMITTED] TP29JY04.018

    Add the ohmic and stray losses, corrected to the reference 
temperature, to give the load loss, Plc2, at the 
reference temperature, by using equation (4-10) as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.020

    The symbols in this section (4.5.3.3) have the following 
meanings:

Ilm(p) is the primary current in amperes,
Ilm(s) is the secondary current in amperes,
Pe is the ohmic loss in the transformer in watts at the 
temperature Tlm,
Pe(p) is the ohmic loss in watts in the primary winding 
at the temperature Tlm,
Pe(s) is the ohmic loss in watts in the secondary winding 
at the temperature Tlm,
Per is the ohmic loss in watts corrected to the reference 
temperature,
Plc1 is the measured load loss in watts, corrected for 
phase angle error, at the temperature Tlm,
Plc2 is the load loss at the reference temperature,
Ps is the stray loss in watts at the temperature 
Tlm,
Psr is the stray loss in watts corrected to the reference 
temperature,
Rdc(p) is the measured dc primary winding resistance in 
ohms,
Rdc(s) is the measured dc secondary winding resistance in 
ohms,
Tk is the critical temperature in degrees Celsius for the 
material of the transformer windings. Where copper is used in both 
primary and secondary windings, Tk is 234.5 [deg]C; where 
aluminum is used in both primary and secondary windings, 
Tk is 225 [deg]C; where both copper and aluminum are used 
in the same transformer, the value of 229 [deg]C is used for 
Tk,
Tk(p) is the critical temperature in degrees Celsius for 
the material of the primary winding: 234.5 [deg]C if copper and 225 
[deg]C if aluminum,
Tk(s) is the critical temperature in degrees Celsius for 
the material of the secondary winding: 234.5 [deg]C if copper and 
225 [deg]C if aluminum,
Tlm is the temperature in degrees Celsius at which the 
load loss is measured,
Tlr is the reference temperature for the load loss in 
degrees Celsius,
Tdc is the temperature in degrees Celsius at which the 
resistance values are measured, and
N1/N2 is the ratio of the number of turns in 
the primary winding (N1) to the number of turns in the 
secondary winding (N2); for a primary winding with taps, 
N1 is the number of turns used when the voltage applied 
to the primary winding is the rated primary voltage.

5.0 Determining the Efficiency Value of the Transformer

    This section presents the equations to use in determining the 
efficiency value of the transformer at the required reference 
conditions and at the specified loading level. The details of 
measurements are described in sections 3.0 and 4.0.

5.1 Output Loading Level Adjustment

    If the output loading level for energy efficiency is different 
from the level at which the load loss power measurements were made, 
then adjust the corrected load loss power, Plc2, by using 
equation 5-1 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.022

Where:

Plc is the adjusted load loss power to the specified 
energy efficiency load level,
Plc2 is as calculated in section 4.5.3.3,
Por is the rated transformer output power (name plate),
Pos is the specified energy efficiency load level, where 
Pos, = PorL2, and
L is the per unit load level, e.g., if the load level is 50 percent 
then ``L'' will be 0.5.

5.2 Total Loss Power Calculation

    Calculate the corrected total loss power by using equation 5-2 
as follows:

[GRAPHIC] [TIFF OMITTED] TP29JY04.019

Where:

Pts is the corrected total loss power adjusted for the 
transformer output loading specified by the standard,
Pnc is as calculated in section 4.4.3.3, and
Plc is as calculated in section 5.1.

5.3 Energy Efficiency Calculation

    Calculate efficiency ([eta]) at specified energy efficiency load 
level, Pos, by using equation 5-3 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.023

Where:

Pos is as described and calculated in section 5.1, and
Pts is as described and calculated in section 5.2.

5.4 Significant Figures in Power Loss and Efficiency Data

    In measured and calculated data, retain enough significant 
figures to provide at least 1 percent resolution in power loss data 
and 0.01 percent resolution in efficiency data.

6.0 Test Equipment Calibration and Certification

6.1 Test Equipment

    Test equipment and measuring instruments must be maintained 
properly, and calibration records must be maintained. The 
calibration of the test set shall confirm the accuracy of the test 
set to that specified in section 2.0.
    The party performing the tests shall control, calibrate and 
maintain measuring and test equipment, whether or not it owns the 
equipment, has the equipment on loan, or the equipment is provided 
by another party. Equipment shall be used in a manner which assures 
that measurement uncertainty

[[Page 45533]]

is known and is consistent with the required measurement capability.

6.2 Calibration and Certification

    The party performing the tests must:
    (a) Identify the measurements to be made, the accuracy required 
(section 2.0) and select the appropriate measurement and test 
equipment;
    (b) At prescribed intervals, or prior to use, identify, check 
and calibrate, if needed, all measuring and test equipment systems 
or devices that affect test accuracy, against certified equipment 
having a known valid relationship to nationally recognized 
standards; where no such standards exist, the basis used for 
calibration must be documented;
    (c) Establish, document and maintain calibration procedures, 
including details of equipment type, identification number, 
location, frequency of checks, check method, acceptance criteria and 
action to be taken when results are unsatisfactory;
    (d) Ensure that the measuring and test equipment is capable of 
the accuracy and precision necessary, taking into account the 
voltage, current and power factor of the transformer under test;
    (e) Identify measuring and test equipment with a suitable 
indicator or approved identification record to show the calibration 
status;
    (f) Maintain calibration records for measuring and test 
equipment;
    (g) Assess and document the validity of previous test results 
when measuring and test equipment is found to be out of calibration;
    (h) Ensure that the environmental conditions are suitable for 
the calibrations, measurements and tests being carried out;
    (i) Ensure that the handling, preservation and storage of 
measuring and test equipment is such that the accuracy and fitness 
for use is maintained; and
    (j) Safeguard measuring and test facilities, including both test 
hardware and test software, from adjustments which would invalidate 
the calibration setting.

Appendix B to Subpart B of Part 432--Sampling Plan for Enforcement 
Testing

    Step 1. The number of units in the sample (m1) shall 
be in accordance with Sec. Sec.  432.13(a)(4), 432.13(a)(5), 
432.13(a)(6) and 432.13(a)(7) and shall not be greater than twenty. 
The number of tests in the first sample (n1) shall be in 
accordance with Sec.  432.13(a)(8) and shall be not fewer than four.
    Step 2. Compute the mean (X1) of the measured energy 
performance of the n1 tests in the first sample by using 
equation 1 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.024

Where Xi is the measured efficiency of test i.

    Step 3. Compute the sample standard deviation (S1) of 
the measured efficiency of the n1 tests in the first 
sample by using equation 2 as follows:

[GRAPHIC] [TIFF OMITTED] TP29JY04.025

    Step 4. Compute the standard error (SE(X1)) of the 
mean efficiency of the first sample by using equation 3 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.026

    Step 5. Compute the sample size discount (SSD(m1)) by 
using equation 4 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.027

Where m1 is the number of units in the sample, and

    RE is the applicable EPCA efficiency when the test is to 
determine compliance with the applicable statutory standard, or is 
the labeled efficiency when the test is to determine compliance with 
the labeled efficiency value.

    Step 6. Compute the lower control limit (LCL1) for 
the mean of the first sample by using equation 5 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.028

Where t is the 2.5th percentile of a t-distribution for a sample 
size of n1, which yields a 97.5 percent confidence level 
for a one-tailed t-test.

    Step 7. Compare the mean of the first sample (X1) 
with the lower control limit (LCL1) to determine one of 
the following:
    (i) If the mean of the first sample is below the lower control 
limit, then the basic model is in non-compliance and testing is at 
an end.
    (ii) If the mean is equal to or greater than the lower control 
limit, no final determination of compliance or non-compliance can be 
made; proceed to Step 8.

    Step 8. Determine the recommended sample size (n) by using 
equation 6 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.029

Where S1 and t have the values used in Steps 3 and 6, 
respectively. The factor
[GRAPHIC] [TIFF OMITTED] TP29JY04.030

is based on a 5-percent tolerance in the total power loss.

    Given the value of n, determine one of the following:
    (i) If the value of n is less than or equal to n1 and 
if the mean energy efficiency of the first sample (X1) is 
equal to or greater than the lower control limit (LCL1), 
the basic model is in compliance and testing is at an end.
    (ii) If the value of n is greater than n1, and no 
additional units are available for testing, testing is at an end and 
the basic model is in non-compliance. If the value of n is greater 
than n1, and additional units are available for testing, 
select a second sample n2. The size of the n2 
sample is determined to be the smallest integer equal to or greater 
than the difference n-n1. If the value of n2 
so calculated is greater than 20-n1, set n2 
equal to 20-n1.
    Step 9. After testing the n2 sample, compute the 
combined mean (X2) of the measured energy performance of 
the n1 and n2 tests of the combined first and 
second samples by using equation 7 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.031

    Step 10. Compute the standard error (SE(X2)) of the 
mean efficiency of the n1 and n2 tests in the 
combined first and second samples by using equation 8 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.032

    (Note that S1 is the value obtained above in Step 3.)
    Step 11. Set the lower control limit (LCL2) to,
    [GRAPHIC] [TIFF OMITTED] TP29JY04.033
    
Where t has the value obtained in Step 5 and SSD(m1) is 
sample size discount from Step 5. Compare the combined sample mean 
(X2) to the lower control limit (LCL2) to find 
one of the following:
    (i) If the mean of the combined sample (X2) is less 
than the lower control limit (LCL2), the basic model is 
in non-compliance and testing is at an end.
    (ii) If the mean of the combined sample (X2) is equal 
to or greater than the lower control limit (LCL2), the 
basic model is in compliance and testing is at an end.

Manufacturer-Option Testing

    If a determination of non-compliance is made in Steps 6, 7 or 
11, above, the manufacturer may request that additional

[[Page 45534]]

testing be conducted, in accordance with the following procedures.
    Step A. The manufacturer requests that an additional number, 
n3, of units be tested, with n3 chosen such 
that n1 + n2 + n3 does not exceed 
20.
    Step B. Compute the mean efficiency, standard error, and lower 
control limit of the new combined sample in accordance with the 
procedures prescribed in Steps 8, 9, and 10, above.
    Step C. Compare the mean performance of the new combined sample 
to the lower control limit (LCL2) to determine one of the 
following:
    (a) If the new combined sample mean is equal to or greater than 
the lower control limit, the basic model is in compliance and 
testing is at an end.
    (b) If the new combined sample mean is less than the lower 
control limit and the value of n1 + n2 + 
n3 is less than 20, the manufacturer may request that 
additional units be tested. The total of all units tested may not 
exceed 20. Steps A, B, and C are then repeated.
    (c) Otherwise, the basic model is determined to be in non-
compliance.

Subpart C--[Reserved]

Subpart D--[Reserved]

[FR Doc. 04-16576 Filed 7-28-04; 8:45 am]
BILLING CODE 6450-01-P