Motor Full Load Current

[Timm1]

The table of full load amperes in NEC states that the current values shall be multiplied by 1.1 and 1.25 for power factors of 0.9 and 0.8 respectively. But in actual practice, we don’t multiply by these factors for the calculations of the motor feeder conductor. I understand that all real motors have a power factor between 0.8-0.9. So I am wondering why we don’t use these factors in practice?

 

[electricpete]

You're talking about 430.250. That note at the bottom applies to the currents given for synchronous machines at unit power factor. It does not apply to the currents given for induction motors.

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