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

[Installer]

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.

 

[wwhitney]

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

Cheers, Wayne

 

[tortuga]

Is that calling for a fuse in the grounded conductor on the 600V disconnect?

 

[infinity]

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.

 

[Dsg319]

This diagram is missing the main bonding jumper for the 600v

 

[infinity]

This diagram is missing the main bonding jumper for the 600v

Yup, there is a note that says "Tie X3, X4 to Neutral and Ground".

 

[Dsg319]

I need to really start reading the notes and not just looking at pictures lol

 

[infinity]

I need to really start reading the notes and not just looking at pictures lol

Lol, it should be shown on the drawing instead of a note.

 

[electrofelon]

You can use that exception where the 600v grounded conductor also serves as your bonding conductor/EGC. Only need to run 2 wires. Don't have my book, 250.30(A) exception?

 

[Installer]

Thanks all

 

[electrofelon]

250.30(A)(1) exception #2 is the section that allows a SBJ on both ends.

 

[tortuga]

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.

 

[electrofelon]

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.

Yes I should have mentioned there are conditions. Another one is the source SDS must be outside.

 

[WD40]

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.

 

[electrofelon]

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.

That's nice because it keeps the L-G voltage lower, but the disadvantage is you still need to run three conductors then.