NEMA Code Letters

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NEMA code letters use letters of the alphabet to represent the amount of locked- rotor amperage (LRA) in kVA per horsepower a motor will draw when it's started. From the table in Fig. 1 notice that letters in the front of the alphabet indicate low LRA ratings, and letters in the back of the alphabet indicate higher LRA ratings. It's important to remember that the number in the table isn't the amount of LRA the motor will draw, but rather it's the number that must he multiplied by the horsepower rating of the motor.

Table with locked-rotor amperage (LRA) ratings. The ratings are listed as amount of kVa per horse power.
Above: Fig. 1: Table with locked-rotor amperage (LRA) ratings. The ratings are listed as amount of kVa per horse power.

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Three Phase Synchronous Motors

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