MV Transformer Protection

[EE123]

Hi,

In a 12kV campus loop setting - how is the transformer protected again short circuit? how is the transformer primary protected?

What protection does the Bayonet fuse provides? what protection does the Current Limiting Fuse in the transformer provides?

Thanks,

 

[cranky108]

The fuse does protect a transformer from a low side fault, but not for over load. The current limiting fuse protects incase of a large fault within the transformer case (keeps the case from rupturing).
The main thing a fuse does is to remove a transformer from a loop, so the remainder of the loop can keep operating.
For these small transformers, they are expendable.

 

[EE123]

Thank you!