US Department of Energy Integral Horsepower Rule, and What It Means for You

NEMA Integral Horsepower Rule

On June 1, 2016, the U.S. Department of Energy’s Integral Horsepower Rule goes into effect. This new rule supersedes the current Energy Independence and Security Act of 2007 that went into effect in December 2010, and many models previously not included in the EISA law will now be required to meet the same efficiency level listed on MG1-2011, Table 12-12. Leading the world in motor efficiency, the DOE has targeted $15 billion in energy savings, while reducing CO2 emissions by millions of tons.

Motors covered under the Integral Horsepower Final Rule meeting include:

  • Single speed motors
  • Rated continuous duty (MG1) operation or for duty type S1 (IEC)
  • Contain a squirrel-cage (MG1) or cage (IEC) rotor
  • Operated on a polyphaser alternating current (ACE) 60-Hertz sinusoidal line power
  • Have 2, 4, 6, 8-pole configuration
  • Rated 600 volts or less
  • Have three or four digit NEMA frame size (or IEC metric equivalent), including those designs between two consecutive NEMA frame sizes (or IEC metric equivalent) or an enclosed 56 NEMA frame size (or IEC metric equivalent)
  • Have no more than 500 horsepower, but greater than or equal to one horsepower (or kilowatt equivalent)
  • Meet all the performance requirements of a NEMA design A, B or C electric motor or an IEC design N or H electric motor

Motors added under the new ruling that were previously not covered by EISA efficiency regulations or other legislation include:

  • Totally enclosed non-ventilated (TENV) AC electric motors
  • 56 frame totally enclosed fan cooled one horsepower and greater
  • Design C motors
  • Footless motors (C-face or D-flange less base)
  • Vertical hollow shaft motors
  • Vertical medium and high thrust solid shaft motors
  • Gearmotors
  • Integral or non-integral brake motors
  • Moisture-resistant windings, sealed or encapsulated windings
  • Motors with non-standard endplates or flanges
  • Partial electric motors
  • 8 Pole 900 RPM motors
  • 56J enclosed jet pump motors

As of June 1, 2016, manufacturers and importers will no longer be able to produce or import listed motors not meeting minimum efficiency requirements shown on MG1-2011, Table 12-12. Models currently identified for upgrade to the new efficiency standards will be permitted to be sold and consumed after the Integral Horsepower Rule takes effect. This allows sellers and users to transition to the higher efficient NEMA Premium® product as required.

Because new, higher-efficiency models require additional raw materials such as copper, and high-grade steel to meet effieciency requirements, you will likely see price increases as the new designs are released. Other new changes include the fact that overall motor length of motor may increase to accommodate these additional materials. In addition certain horsepower ratings can expect an increase in frame size. Check with your motor supplier for dimensional changes and new model number replacements.

Motors excluded from the Integral Horsepower Rule include:

  • Single Phase open drip proof motors (small motor rule may apply)
  • Single phase enclosed motors
  • 42-48 frame motors (small motor rule may apply)
  • 56 frame open drip motors (small motor rule may apply)
  • Multi-speed motors
  • Totally enclosed air over (TEAO) motors
  • Medium voltage motors
  • Submersible motors
  • Intermittent duty motors (S2-S8)
  • Stator Rotor sets
  • Design D motors
  • Motors designed to run on inverter power (MG1 part 31) listed with no line start
  • AC Synchronous motors
  • Permanent Magnet AC motors
  • Servo Motors

For more information on the Integral Horsepower rule, please contact your Kaman representative, or by commenting on this post in the comments section below.

For more information on IHP, please use the following resources:

NEMA Integral Horsepower Rule Webinar >>
Baldor Energy Savings >>

Estimated Reading Time: 2 minutes

Mike Polo

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