Understand the New Motor Standards

Regulations will require higher energy efficiency for many AC motors.

By John Malinowski, Baldor Electric Co.

1 of 2 < 1 | 2 View on one page

Motors manufactured after December 19, 2010, for sale in the United States are affected by the Energy Independence and Security Act of 2007 (EISA). EISA was passed by Congress and signed into law on December 19, 2007. EISA builds upon the Energy Policy Act of 1992 (EPAct) by raising mandated efficiency standards for general-purpose three-phase 1–500-hp. AC industrial motors.

Standards for each general-purpose rating (subtype I) from 1 to 200 hp. previously covered by EPAct increase to the nominal full-load efficiency level for "NEMA Premium" given in Table 12-12 in NEMA "Motors and Generators," Revision 1 (MG 1 - 2009) — see Table 1. (For more information on the standards, go to www.nema.org/stds/mg1.cfm.) These are 230/460-V., 60-Hz., Design B, 2-, 4- or 6-pole AC induction motors.

>>>>> Register for Lifecycle Management of High Voltage Motors to Optimize Cost  of Ownership Webinar

General-purpose electric motors (subtype II) previously not covered by EPAct must meet efficiencies defined in Table 12-11 in MG 1 (Table 2). These motors incorporate design elements of a subtype-I general-purpose unit but are configured as one of the following:
• U-frame motor;
• Design C motor;
• close-coupled pump motor;
• C-face or D-flange footless motor;
• vertical solid-shaft normal thrust motor (as tested in a horizontal configuration);
• an eight-pole motor (900 rpm);
• a poly-phase motor of not more than 600 V. (other than 230 or 460 V.); and
• 201–500-hp. motors previously not covered by EPAct.
EISA-mandated efficiency levels for subtype-I motors fall within efficiencies of existing general-purpose 1–200-hp. NEMA Premium efficient motors, such as Baldor's Super-E.

Manufacturers of some designs of subtype-II 1–200-hp. and general-purpose 201–500-hp. motors may have to raise their efficiency; however, many designs may already comply. NEMA Premium efficient motors meet or exceed EISA requirements for either of these motor types.

EISA doesn't apply to fractional-hp. and 48- or 56-frame motors. It only covers 1–500-hp. motors with three-digit frame NEMA numbers (143T and up) or equivalent IEC designations of frames 90 and larger (excluding IEC100).

Not every three-phase 1–500-hp. motor configuration falls under EISA — but almost all motors except some special OEM designs with proprietary mounting configurations do. The following configurations are exempt from EISA compliance:

1 of 2 < 1 | 2 View on one page
Show Comments
Hide Comments

Join the discussion

We welcome your thoughtful comments.
All comments will display your user name.

Want to participate in the discussion?

Register for free

Log in for complete access.


No one has commented on this page yet.

RSS feed for comments on this page | RSS feed for all comments