Power Transformer LV Coordination - Inrush

[BuggyBrent]

I have a 10 MVA, 69/13.2 kV transformer. It has HS and LS fuses. My question is how concerned should I be that the LS fuse coordinates with the transformers inrush curve? Do the LS devices actually see the curve or is it seen only from the HS devices? I have not found a definitive answer through various text books.

 

[davidbeach]

Can you energize the transformer from the low-side?

 

[Skogsgurra]

The inrush is a business strictly between HS side and line. You can have funny voltages on the low side during the inrush. But nothing that the LS fuses care about.

Gunnar Englund

http://www.gke.org

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Half full - Half empty? I don't mind. It's what in it that counts.

 

[RRaghunath]

The coordination is only for through fault currents.
The Transformer energisation inrush is felt only by the fuses on the source side of the transformer.

 

[BuggyBrent]

In most cases, the transformer will not be energized from the low-side.

I thank everyone for their posts.