10 CFR Appendix B
Uniform Test Method for Measuring Nominal Full Load Efficiency of Electric Motors
June 9, 2020
CFR

Note: After June 11, 2014, any representations made with respect to the energy use or efficiency of electric motors for which energy conservation standards are currently provided at 10 CFR 431.25 must be made in accordance with the results of testing pursuant to this appendix.

For manufacturers conducting tests of motors for which energy conservation standards are provided at 10 CFR 431.25, after January 13, 2014 and prior to June 11, 2014, manufacturers must conduct such test in accordance with either this appendix or appendix B as it appeared at 10 CFR Part 431, subpart B, appendix B, in the 10 CFR Parts 200 to 499 edition revised as of January 1, 2013. Any representations made with respect to the energy use or efficiency of such electric motors must be in accordance with whichever version is selected. Given that after June 11, 2014 representations with respect to the energy use or efficiency of electric motors must be made in accordance with tests conducted pursuant to this appendix, manufacturers may wish to begin using this test procedure as soon as possible.

For any other electric motor type that is not currently covered by the energy conservation standards at 10 CFR 431.25, manufacturers of this equipment will need to use Appendix B 180 days after the effective date of the final rule adopting energy conservation standards for these motors.

1. Definitions.

Definitions contained in §§431.2 and 431.12 are applicable to this appendix.

2. Test Procedures.

Efficiency and losses shall be determined in accordance with NEMA MG1-2009, paragraph 12.58.1, “Determination of Motor Efficiency and Losses,” (incorporated by reference, see §431.15) and either:

(1) CSA C390-10, (incorporated by reference, see §431.15), or

(2) IEEE Std 112-2004 Test Method B, Input-Output With Loss Segregation, (incorporated by reference, see §431.15).

3. Amendments to test procedures.

Any revision to IEEE Std 112-2004 Test Method B, NEMA MG1-2009, or CSA C390-10, (incorporated by reference, see §431.15) shall not be effective for purposes of certification and compliance testing unless and until this appendix and 10 CFR Part 431 are amended to incorporate that revision.

4.   Procedures for the Testing of Certain Electric Motor Types.

Prior to testing according to IEEE Std 112-2004 (Test Method B) or CSA C390-10 (incorporated by reference, see §431.15), each basic model of the electric motor types listed below must be set up in accordance with the instructions of this section to ensure consistent test results. These steps are designed to enable a motor to be attached to a dynamometer and run continuously for testing purposes. For the purposes of this appendix, a “standard bearing” is a 6000 series, either open or grease-lubricated double-shielded, single-row, deep groove, radial ball bearing.

4.1   Brake Electric Motors:

Brake electric motors shall be tested with the brake component powered separately from the motor such that it does not activate during testing. Additionally, for any 10-minute period during the test and while the brake is being powered such that it remains disengaged from the motor shaft, record the power consumed (i.e., watts). Only power used to drive the motor is to be included in the efficiency calculation; power supplied to prevent the brake from engaging is not included in this calculation. In lieu of powering the brake separately, the brake may be disengaged mechanically, if such a mechanism exists and if the use of this mechanism does not yield a different efficiency value than separately powering the brake electrically.

4.2   Close-Coupled Pump Electric Motors and Electric Motors with Single or Double Shaft Extensions of Non-Standard Dimensions or Design:

To attach the unit under test to a dynamometer, close-coupled pump electric motors and electric motors with single or double shaft extensions of non-standard dimensions or design must be tested using a special coupling adapter.

4.3   Electric Motors with Non-Standard Endshields or Flanges:

If it is not possible to connect the electric motor to a dynamometer with the non-standard endshield or flange in place, the testing laboratory shall replace the non-standard endshield or flange with an endshield or flange meeting NEMA or IEC specifications. The replacement component should be obtained from the manufacturer or, if the manufacturer chooses, machined by the testing laboratory after consulting with the manufacturer regarding the critical characteristics of the endshield.

4.4   Electric Motors with Non-Standard Bases, Feet or Mounting Configurations

An electric motor with a non-standard base, feet, or mounting configuration may be mounted on the test equipment using adaptive fixtures for testing as long as the mounting or use of adaptive mounting fixtures does not have an adverse impact on the performance of the electric motor, particularly on the cooling of the motor.

4.5   Electric Motors with a Separately-powered Blower:

For electric motors furnished with a separately-powered blower, the losses from the blower's motor should not be included in any efficiency calculation. This can be done either by powering the blower's motor by a source separate from the source powering the electric motor under test or by connecting leads such that they only measure the power of the motor under test.

4.6   Immersible Electric Motors

Immersible electric motors shall be tested with all contact seals removed but be otherwise unmodified.

4.7   Partial Electric Motors:

Partial electric motors shall be disconnected from their mated piece of equipment. After disconnection from the equipment, standard bearings and/or endshields shall be added to the motor, such that it is capable of operation. If an endshield is necessary, an endshield meeting NEMA or IEC specifications should be obtained from the manufacturer or, if the manufacturer chooses, machined by the testing laboratory after consulting with the manufacturer regarding the critical characteristics of the endshield.

4.8   Vertical Electric Motors and Electric Motors with Bearings Incapable of Horizontal Operation:

Vertical electric motors and electric motors with thrust bearings shall be tested in a horizontal or vertical configuration in accordance with IEEE 112 (Test Method B), depending on the testing facility's capabilities and construction of the motor, except if the motor is a vertical solid shaft normal thrust general purpose electric motor (subtype II), in which case it shall be tested in a horizontal configuration in accordance with IEEE 112 (Test Method B). Preference shall be given to testing a motor in its native orientation. If the unit under test cannot be reoriented horizontally due to its bearing construction, the electric motor's bearing(s) shall be removed and replaced with standard bearings. If the unit under test contains oil-lubricated bearings, its bearings shall be removed and replaced with standard bearings. Finally, if the unit under test contains a hollow shaft, a solid shaft shall be inserted, bolted to the non-drive end of the motor and welded on the drive end. Enough clearance shall be maintained such that attachment to a dynamometer is possible.

[77 FR 26638, May 4, 2012, as amended at 78 FR 75994, Dec. 13, 2013]


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