Xfrmr Rating

Status
Not open for further replies.
A

Alwayslearningelec

Senior Member
Location
NJ
Occupation
Estimator
200A 277/480v circuit breaker feeding a 150KVA step down xfrmr to feed two 200A panels.

Could I put a trough by the secondary side of the xfrmr and tap to feed (2) 200A panels right next to it?
 
horsegoer said:
200A 277/480v circuit breaker feeding a 150KVA step down xfrmr to feed two 200A panels.

Could I put a trough by the secondary side of the xfrmr and tap to feed (2) 200A panels right next to it?
Click to expand...

You can certainly use a piece of wireway in lieu of conduit, if that is what you are asking.

But you don't get a free pass to do as you please. There are some requirements you still have to meet, basically the same as if you were using conduit.
 
Pay attention to the rules in 240.21(C). The secondary conductors cannot be tapped in trough, the panel feeders would need to originate on the transformer terminations.
 
jim dungar said:
Pay attention to the rules in 240.21(C). The secondary conductors cannot be tapped in trough, the panel feeders would need to originate on the transformer terminations.
Click to expand...
good point.

it did not occur to me that the OP might want to make the tap inside the trough. his post is pretty vague on that issue.
 
jim dungar said:
Pay attention to the rules in 240.21(C). The secondary conductors cannot be tapped in trough, the panel feeders would need to originate on the transformer terminations.
Click to expand...
so you can feed two panels for one xfrmr . need to feed one panel and then a breaker in the panel would feed the other panel?
 
There is a lot left unsaid in the OP.

I think most of us are assuming the OP has a 480 to 208/120 3 phase transformer, even though he does not say so.

The OP does not say the panels are MCB, although most of us are probably assuming they are.

We are also assuming he can meet the applicable requirements of 240.21(C) [IRRC] and all he wants to do is use a piece of wireway instead of conduit.

Those are all "reasonable" assumptions, but not something the OP actually stated.
 
Status
Not open for further replies.
Top