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Short term step up

Short term step up

Short term step up

(OP)
Our shop has 240 3 ph 60 Hz, and we need to run a short term (several 5 minute tests) on some equipment needing 480 3 ph.  

We have a disconnected distribution transformer, 480 Y / 240 delta 150 A secondary, which is at least 30 times the ampacity needed for the test.  

Is it OK to backfeed 240 into this to obtain the 480??

Thanks in advance!

RE: Short term step up

Yes, but there are various code rules that would have to be complied with.

RE: Short term step up

Your initial current inrush may be over 1000 Amps. You may need dual element fuses to get this energized.
 

Bill
--------------------
"Why not the best?"
Jimmy Carter

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