Medium-Voltage Trasnformer load interrupter switch

[skeshesh]

Hello everyone, hope all is well.

Can someone point me to a good technical document about load interrupter switchs applied to the primary of medium voltage transformers. The specific case is a upgrading a 12kV-277/480V transformer to serve new mechanical loads and it's not a very complicated case but I'd like to dig into the subject for a deeper understanding. Your help and comments are much appreciated.

 

[weressl]

Hello everyone, hope all is well.

Can someone point me to a good technical document about load interrupter switchs applied to the primary of medium voltage transformers. The specific case is a upgrading a 12kV-277/480V transformer to serve new mechanical loads and it's not a very complicated case but I'd like to dig into the subject for a deeper understanding. Your help and comments are much appreciated.

IEEE 141-1993 Red Book, Power Distribution
IEEE 241 Buff Book, Protection and Coordination
Eaton, Siemens websites

 

[zog]

Hello everyone, hope all is well.

Can someone point me to a good technical document about load interrupter switchs applied to the primary of medium voltage transformers. The specific case is a upgrading a 12kV-277/480V transformer to serve new mechanical loads and it's not a very complicated case but I'd like to dig into the subject for a deeper understanding. Your help and comments are much appreciated.

What exactly are you looking for? What is the switch nameplate info? Likely I have the exact manual for your switch that will have all of the specs and instructions.

 

[skeshesh]

Thanks much Laszlo, I'll go dig those out of our library.

Zag - I may or may not ask to replace the existing switch, I have to do more research. The existing 75KVA xfmr is not adequate to serve the new mechanical loads. I got the mechanical data recently, plus the client just found the electrical as builts which they sent me. Prior to that, upgrading the transformer was unnecessary so I had not field-investigated the primary switch. The as-builts show a "3P-600A Loadbreak Switch" but no other information is specified; neither is the fuse size. In any case, I rather see (or have someone verify) what's installed in the field. The job site is a 5 hour drive so I'll have to wait for a good time to get down there, but when I get that info I will certainly take advantage of your kind offer for the manual. The next submittal is next week but its partial so I'll have some more time to find all the necessary data before the final submittals.

 

[jghrist]

A 600A loadbreak switch should be more than adequate to break load on a larger transformer. Full load on 75 kVA is only 3.6A at 12 kV.