Calculating Motor Full Load Rating
Calculating Motor Full Load Rating
(OP)
Can anyone tell me why the full load amps listed in the NEC do not equal the motor power rating divided by the motor voltage rating? For instance, a 10hp 230V single phase motor is rated at 50Amps according to NEC, but using I=V/P, you get 32Amps.





RE: Calculating Motor Full Load Rating
RE: Calculating Motor Full Load Rating
=====================================
(2B)+(2B)' ?
RE: Calculating Motor Full Load Rating
----------------------------------
If we learn from our mistakes I'm getting a great education!
RE: Calculating Motor Full Load Rating
Try comparing NEC to the nameplate of an actual 10 HP, 1 Ph, 230V motor.
Rafiq Bulsara
http://www.srengineersct.com
RE: Calculating Motor Full Load Rating
I looked at Reliance's site and I couldn't find any single-phase 10hp motor....
But here is a 5hp single phase 230vac motor:
http
FLA of the 5hp motor is 30.
If you doubled that for 10hp motor, you'd expect 60A.
If you allow for better efficiency and power factor on the 10hp than the 5hp, 50A might be reasonable.
=====================================
(2B)+(2B)' ?
RE: Calculating Motor Full Load Rating
=====================================
(2B)+(2B)' ?