Main breaker feed meeting code
Main breaker feed meeting code
(OP)
We are feeding a main breaker in a MV switchgear line-up by a secondary side of a transformer. We want to use the same feed to feed an other breaker. In doing that, we would be running a cable from source side of main breaker, to the new breaker, instead of feeding the new breaker directly from the transformer. I couldn't find anything in the code agains this design. Does anyone know of any code requirement that is applicable to this situation? Thanks in advance!






RE: Main breaker feed meeting code
RE: Main breaker feed meeting code
RE: Main breaker feed meeting code
Also, it appears you have a 2000A main, but what is the size of the conductors feeding that main? If you want to tap off for 400A, your conductors must be capable of 2400A, both for the ones feeding the main and the ones feeding the 400A breaker. Then you have to look at whether or not the 400A breaker can hold those conductors.
By the way, this is what switchgear is for.
"Dear future generations: Please accept our apologies. We were rolling drunk on petroleum."
— Kilgore Trout (via Kurt Vonnegut)
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies
RE: Main breaker feed meeting code
Going back to the feeder size issue, the new breaker is 1200A. The feeder to main is rated for 3600A (3-1/C #1000 MV-105 copper). The new breaker is 1200A. The feeder to the new breaker is rated for 1200A. Did you mean it has to be rated for 3600A? The load this new breaker is feeding is only 800A.
RE: Main breaker feed meeting code
RE: Main breaker feed meeting code