7anoter4 - what CB are you referring to?
The primary conductors are protected by a 100E fuse. Clearing time at Isc (say 26.5kA) for a 100E (per trip this curve) should be ~0.01 if I'm looking at it correctly.
Please set me straight if I am interpreting this incorrectly. [thanks]
7anoter4 - Wow, a 316 MCM seems like overkill imho just based off of the installations I have seen in the field. But that doesn't mean that the installations I looked at were correct though.
Also - It looks like the calculation you provided for short circuit of a 500MVA transformer is actually...
Hey - I'm supposed to be asking the questions here... Only joking of course.
I have not found anywhere in the Code that indicates a need to rate the primary conductors for 125% of the transformer load.
I would expect that to be the case but I haven't found it. I would love for someone point...
I figured someone would say that :)
I almost added to my post that I would go with a #2 because that is the smallest stocked conductor (by Okonite).
For this particular application it is a moot point - I agree.
-BUT-
For future applications I would like to have a solid grasp on the code so...
Hello all,
I have a 1500kVA 12.47kV to 480V 3 phase transformer being installed and I was tasked with verifying the primary feeder sizing. I found another post that very closely described the situation I am facing but I have some additional questions. The transformer is being fed by a fused...
