hello,
this is the most reilable place on the WEB for electricians. and i can not say this enough.
This is my case:
i am working on sizing supply conductors and main circuit breaker to supply a resistance welder machine.
with the following loads
6 Tranformers of 120 kva
3 Tranformers of 85 Kva
5 Motors 3 pahse 460 vFull load current is 2.5 amp .
this is my procedure for conductor sizing:
1 - (120kva/480)*.7 = 175*6 = 1050 AMP
2- (85kva/480)*.7 = 124*3 = 372 AMP
3- Motors = (2.5*1.25)+(2.5*4) = 13.125 AMP
is this is correct? what should i go a bout sizing the circuit breaker.
the reason why i am not sure about the above calculation is the current circuit breaker size is 400 amp and the wire size is 500 Kcmill. and the breaker is not tripping.
Thank you for your help
this is the most reilable place on the WEB for electricians. and i can not say this enough.
This is my case:
i am working on sizing supply conductors and main circuit breaker to supply a resistance welder machine.
with the following loads
6 Tranformers of 120 kva
3 Tranformers of 85 Kva
5 Motors 3 pahse 460 vFull load current is 2.5 amp .
this is my procedure for conductor sizing:
1 - (120kva/480)*.7 = 175*6 = 1050 AMP
2- (85kva/480)*.7 = 124*3 = 372 AMP
3- Motors = (2.5*1.25)+(2.5*4) = 13.125 AMP
is this is correct? what should i go a bout sizing the circuit breaker.
the reason why i am not sure about the above calculation is the current circuit breaker size is 400 amp and the wire size is 500 Kcmill. and the breaker is not tripping.
Thank you for your help