Protection Guidelines

[mutimuti]

I am looking for guidelines for protecting distribution systtem networks, especially between 11kV (possibly lower) and 66kV. In particular explicit information on when to use fuses or a combination of fuse and circuit breaker.

Thank you.

 

[alehman]

This is a rather vague question. There are many books on the subject of distribution protection. Take a look at faq238-1287

The IEEE Red Book, Buff Book and Blackburn's Protective Relaying are all good starting points.

 

[PHILEC]

In MV system like 13.8kv and below, we normally used fused-contactor line-up in the outgoing feeder instead of circuit breakers for economical reason, but this is valid only for resistance grounded system in the secondary of delta-wye incomer transformer. The fuse will protect the feeders from high short circuit currents i.e. 3phase and Line to line while the contactor will be opened only for overloads and ground faults. The contactor should be latched-in type so that it will not open during 3phase and line to line short circuit.

In this system, fuse cannot be used on the primary side of delta-wye incomer transformer because it cannot backup for a ground fault on the secondary side of transformer, because the ground fault at the secondary side of delta-wye transformer is seen as a line to line fault on the primary side.Instead of fuse use circuit breaker on the primary side.

 

[Denan]

Try this:

http://www.geindustrial.com/pm/notes/artsci/

Hope it helps!

Denan

 

[bigswitch]

http://www.areva-td.com/servlet/Con...48589697&lid=en&tab=Chapters&id=1056536208254

some useful information on here!

 

[olicg]

In IEEE Color Book series, there is one in particular on Distribution IEEE - 141. This nearly 800 page book/standard is an excellent document to read.

 

[stevenal]

Talk to your Cooper rep about getting a copy of Electrical Distribution System Protection.