120/240V Single Phase Transformer Current

[nedster]

HI all,

Just wondering when sizing a conductor on a 120/240V Single Phase Three wire transformer, why do you use the 240V and not 120V to divide the KVA with to find the current value.

 

[charlie b]

Re: 120/240V Single Phase Transformer Current

Because the KVA value represents the load (i.e., ?apparent power?) on the entire transformer. As viewed by the outside world, the transformer is supplying that power at 240 volts.