Another Delta question

[craig65]

I have corrected the wiring on the transformer as discussed in my last post.
the results are:
on the delta side...42A on A phase, 42A on B phase OA on C phase, 1.5A on the ground. All gounds bonded in the transformer, no neutral connection and no jumper to XO from ground
A phase is corner ground.
the new problem is:
I can get breakers to trip now, all but one anyway.
One of the breakers trips 90% of the time. Just makes noise the other 10%

on the wye side at the transformer....57A on A phase, 120A on B phase and 60A on C phase.
would a jumper from ground to XO correct this?
Any Ideas???

 

[jim dungar]

...on the wye side at the transformer....57A on A phase, 120A on B phase and 60A on C phase.
would a jumper from ground to XO correct this?

Do not jumper X0 to ground or to neutral, when using a step up wye-delta transformer. The unbalance on the wye side is due to your extreme, single phase, unbalance on the delta side.

 

[augie47]

Curious, what are your loads on the delta side. 0 current on C phase ?

 

[craig65]

Curious, what are your loads on the delta side. 0 current on C phase ?

Yes... 0 on C phase on delta side 60 on the wye side. the loads in the delta panel are split between A and B phase @ 42 A each