GFI breaker protection

[hurk27]

The '4,000 amp main' has been cut from its source of supply and re-fed from a feeder that has GFP.

Everything supplied from that 4000 amp gear is now GFPed.

My thinking was in Post #3 the Op'er stated that he has 4 4,000 amp services throughout this complex which can be quite normal for a large venue? Post one he is calling the 4000 amp breaker a service main so between the two post the complex sounds like it has 4 4000 amp MDP's with 4000 amp GFP mains in each, also in post 7 he mentioned that he had breakers from 60 to 1200 amp in these panels which is why I figured that the 1000 amp and 1200 amp breakers had to be feeders because he mentioned about having the 4000 amp mains.

Did I miss something? I know when I get home from the mill I can be very tired, and miss read things or read more into it then what is there LOL

Also I was thinking he was mixing the fact that all these breakers being 100AIC rated was a coordinated system and is why I made my comment in post 16, as having all the breakers in the same panel is called a fully rated system or 100%rated which is why I pointed out that AIC rating has nothing to do with selective coordination.

 

[zog]

Thanks for the input.
We have a 4000 amp main with GFI protection installed in that one switchboard there is a 1000 amp and a 1200 amp breaker each of these in fact all breakers in all our switchboards are 100 % rated typical AIC which matches the 4000amp main its 100K AIC rated and each breaker from 60 amp to 1200 amp has a 100k AIC rating so there is no breaker less than the main breaker AIC . Its 100 percent rated gear the coordination is the low settings down stream per engineer .

So can the inspector require me to put a GFI on the down stream breakers in switchboard has something change I may not be aware of .

You are confusing GFI with GFP, 2 very different things with different purposes. AIC ratings are a whole different topic and has little to do with GFP.