120 to 600 VAC Step up Transformer connection-- Hot & G or Hot & N?

Installer

Senior Member
We're using a GE 5 KVA Step -Up transformer with 120 VAC on the source side, 600 VAC on the high side.
The panel is a 120/208 three phase Wye .
On the source side of the Step Up Transformer does one of the hot legs go to the Breaker and the other to ground?
or
does one of the hot legs go to the Breaker and the other to neutral?
What would be the reasoning. I'm on an island off the coast of Alaska with limited internet access -and I don't have my books.
Thank you in advance for any help offered.

120 to 600 .png
 
The conductor connected to X1 will carry current in normal operation. So it must be the neutral circuit conductor, not the EGC.

Cheers, Wayne
 
On the source side of the Step Up Transformer does one of the hot legs go to the Breaker and the other to ground?
A 120 volt circuit would never use the EGC as a current carrying conductor so it must be a neutral.

The H4 is missing the system bonding jumper.
 
250.30(A)(1) exception #2 is the section that allows a SBJ on both ends.
Yeah as long as there are no parallel paths like comms or metal pipe, and the fuse in the grounded 600V conductor is a 240.22 violation so I bet they had it drawn as a ungrounded system then decided to ground it and did not update the drawing fully.
 
I did one like years back and if I recall correctly the 600V step up side had a center tap that I connected to ground.
 
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