Multipoint grounded neutral, generator connection
Multipoint grounded neutral, generator connection
(OP)
A facility as a 12.47kV ring bus supplying (20) wye-wye transformers, solidly grounded with a common neutral (multipoint grounded neutral). The facility purchased a 3MVA 12.47kV generator to be connected and synchronized with the ring bus and offset a portion of their utility usage. Per the generator manufacturer the generator must be wye-impedance grounded.
Are there any options other than adding a 12.47kV/12.47kV isolation transformer to develop a separately derived system to satisfy the NEC?
Thanks!
Are there any options other than adding a 12.47kV/12.47kV isolation transformer to develop a separately derived system to satisfy the NEC?
Thanks!






RE: Multipoint grounded neutral, generator connection
RE: Multipoint grounded neutral, generator connection
We have to trip all our direct connect generators for system ground faults (they are small), where we can locate the ground faults as system faults on units connected through a wye-delta GSU.
3MVA at 12.47?? I would have expected 4160 for that size.
RE: Multipoint grounded neutral, generator connection
M. Nissen,P.E.
Senior Electrical Engineer
Waldron Engineering & Construction
RE: Multipoint grounded neutral, generator connection
RE: Multipoint grounded neutral, generator connection
Bill
--------------------
"Why not the best?"
Jimmy Carter