Dustin Foelber
Senior Member
I have a project where we replaced the existing utility transformer with a new 3000 amp switchgear. The old transformer was feeding a 1200 Amp gear. We intercepted the conduits coming from that gear and reworked them into our new 3000 amp gear. I then repulled a triple feed of 600 MCMs to refeed the old 1200 amp gear. I am feeding it with a 1200 Amp subfeed breaker at the new gear and the 1200 amp gear also has a main breaker.
Here is my question/mistake.
When I pulled the triple 600 MCM I sized my ground to the individual run and not to the 1200 amp overcurrent. Basically I ran a 2 AWG instead of the required 1/0 per the paralell full size ground requirements. I am wondering because it is a seperate structure and is grounded seperately (no nuetral bond but has its own UFER and CW grounds) is there any exception anyone is aware of where the number 2 ground can be considered adequate? I really appreciate your help guys.
Dustin-
Here is my question/mistake.
When I pulled the triple 600 MCM I sized my ground to the individual run and not to the 1200 amp overcurrent. Basically I ran a 2 AWG instead of the required 1/0 per the paralell full size ground requirements. I am wondering because it is a seperate structure and is grounded seperately (no nuetral bond but has its own UFER and CW grounds) is there any exception anyone is aware of where the number 2 ground can be considered adequate? I really appreciate your help guys.
Dustin-
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