dry type transformer

[peterrudart]

how do i wire a 45kva 3p 208/ 208 120 transformer? do i make a case bond to the xo bar? do i need a neutral from my primary feed?

 

[GoldDigger]

how do i wire a 45kva 3p 208/ 208 120 transformer? do i make a case bond to the xo bar? do i need a neutral from my primary feed?

You appear to be describing a delta to wye transformer. Is the delta side the input? So the X0 lead would be on the secondary side?

If the primary is delta, you do not need a primary neutral, but you must provide a ground/EGC bonded to the secondary neutral.

 

[augie47]

This may help (diagram is single phase but same principles)

 

[peterrudart]

iso ground?

iso ground?

So the whole purpose of the transformer is to get an isolated groung, where and how can I make that happen?

 

[infinity]

I responded to the that same question here:

http://forums.mikeholt.com/showthread.php?t=156169