Ungrounded Wye Distribution

[ekc08]

So I overheard some people from another utility saying that they have ungrounded wye on their distribution system. They also mentioned having to order special transformers and incorrect tap ratios on the transformers resulting in poor voltage to customers. I am interested in learning more, but have not been able to find much helpful information thus far. Can anyone tell me more about how an ungrounded wye system works? If there is no neutral for a return path for fault current, does this pose a danger to line workers?

 

[davidbeach]

Ungrounded is ungrounded, doesn't matter if it comes from a wye or a delta. There have been many threads in this forum discussing ungrounded systems. Read up and then come back with a few specific questions rather the very broad questions initially asked.

 

[waross]

If the system runs three wires it doesn't matter whether it is fed from wye or delta.
If the neutral is carried out, (4 wire system) it should be insulated for line to line neutral voltage and the phase wires must be insulated for line to line voltage rather than line to neutral voltage. That would be spending extra money to get incur extra issues.
But, what David says, more information please.

Bill
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"Why not the best?"
Jimmy Carter