Branch Circuits

[Echoengineer]

I've recently ran into an issue on a project that I'm working when sizing a panelboard that can accommodate the customers needs. Here is the situation. I have a 300kva pad mount transformer that provides 480Vac to a 400A service disconnect. From this disconnect I have sized a panel from Eaton, PRL3X that has a 600A bus with a 400A ECB main. The specs of this panel indicate an max branch circuit rating of only 225A. Customer has a 200HP pump that requires at minimum a 300A OCPD. Would it be allowable to use a 300A branch circuit when the panel is rated to support a max of 225A?

 

[infinity]

The specs of this panel indicate an max branch circuit rating of only 225A.

Can this panel be fitting with feed thru lugs? If so just feed a 400 fused disconnect and install 300 amp fuses.

 

[JoeStillman]

The specs of this panel indicate a max branch circuit rating of only 225A.

Your 300A breaker is going to be a 400A frame (same physical size, different trip rating). The spacing of the 225A horizontal bus fingers will not be wide enough for the bigger breaker.

 

[jaggedben]

Do a feeder tap ahead of the panel?

 

[electrofelon]

Yeah just use feed thru or subfeed lugs to a separate disco. The lugs Should be an easy thing to add / swap out. Or you'd have to get a panel board that can take a 400 amp frame.