2 Pole va calc on 208v 3ph system question

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heelex

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Hello

Question is - What is the correct va calculation for a 2 pole 60 amp cct. at 208 volts. I get 12,480 va. (208x60)
Peng says it's 14,400 va (2x120Vx60)

It is a 2 pole breaker in a 3 ph panel.

Thanks for any reply's
 
My response is based on the inference that this is a circuit that does not have a neutral, and more to the point it is not a MWBC. I also infer that the load is 60 amps, as opposed to a 60 amp breaker serving a load that draws something less than 60 amps. You have it right. The voltage across the circuit is 208, not 240, and not a pair of 120's.

If this were a MWBC, and if it served two independent 120 volt loads, then the other person would be right.
 
charlie b said:
My response is based on the inference that this is a circuit that does not have a neutral, and more to the point it is not a MWBC. I also infer that the load is 60 amps, as opposed to a 60 amp breaker serving a load that draws something less than 60 amps. You have it right. The voltage across the circuit is 208, not 240, and not a pair of 120's.

If this were a MWBC, and if it served two independent 120 volt loads, then the other person would be right.
Click to expand...


Thanks for your reply.
The breaker will feed a 60 amp 120/240 v 3 wire receptacle which will have a single phase temporary panel plugged into it.
What is 'MWBC'?
 
heelex said:
Thanks for your reply.
The breaker will feed a 60 amp 120/240 v 3 wire receptacle which will have a single phase temporary panel plugged into it.
What is 'MWBC'?
Click to expand...
MWBC is multiwire branch circuit, which what you have described seems to be if one wire is a system neutral.

I'd take the higher VA calc' into consideration if you don't know what all is going to be fed by the temp panel.
 
heelex said:
Hello

Question is - What is the correct va calculation for a 2 pole 60 amp cct. at 208 volts. I get 12,480 va. (208x60)
Peng says it's 14,400 va (2x120Vx60)

It is a 2 pole breaker in a 3 ph panel.

Thanks for any reply's
Click to expand...

Im trying to think why the P.Eng said 14,400?

For 2 Pole cct:
P=V(p-p)*I
= 208*60 = 12480

Unless this is for a residential panel in which case P=240*60, but you clearly state 208V,3Ph system so not residential panel?
 
ElectDesigner said:
Im trying to think why the P.Eng said 14,400?

For 2 Pole cct:
P=V(p-p)*I
= 208*60 = 12480

Unless this is for a residential panel in which case P=240*60, but you clearly state 208V,3Ph system so not residential panel?
Click to expand...
Sounds like the receptacle is going to supply a 120/208 1? 3W panel via a receptacle.

Potential max connected load is 60A?120V?2Lines=14,400VA
 
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