Voltage Drop including Motors

[bvano1983]

Im an electrical student and have a question. When calculating voltage drop for conductors supplying a motor. Do you still calculate the FLC at 125%? The illustrated guide says to not calculate at 125%.

Someone tell me some real world answers.

 

[DetroitEE]

The 125% you reference is typically used to size the conductors supplying the motor, not the actual full load current. The Ffull load current values are given in tables in the NEC; I would use these values for voltage drop calculations, and I would not multiply them by 125% for the sake of the calculation.

 

[raider1]

I agree with DetroitEE,

The 125% is used to size conductors that terminate on a breaker that is rated for 80%. For voltage drop just use the FLA of the motor and don't add the 25%.

Chris