Neutral Currents in a Wye:g Transformer

[ChrisCentral]

I have an incoming service to a building at 347/600V Wye:g, 600A. A contractor has installed a step down transformer 347/600V to 480V Delta, the inspector passed the installation but now the transformer is overheating and there are both Neutral and Ground currents. I read through 'The Wyes of Wyes' but I can't get a clear answer on the issue - to make matters worse the transformer mfg doesn't 'necessarily see a problem with the connection as it has been completed'.... please help :?

 

[david luchini]

Remove the neutral conductor from the primary side of the transformer.

 

[david luchini]

Oh, and also remove the neutral point to transformer enclosure bond on the primary.

 

[Sahib]

I think your idea is to break the path for stray current through the transformer. But disconnecting primary neutral ground connection will give rise to unsymmetrical secondary voltages for unbalanced loads on a wye wye transformer.

 

[mivey]

Remove the neutral conductor from the primary side of the transformer.

I agree it is acting like a grounding bank.

 

[mivey]

But disconnecting primary neutral ground connection will give rise to unsymmetrical secondary voltages for unbalanced loads on a wye wye transformer.

Then it is a good thing that is not a concern for the OP since that is not what the OP has.