Is the min. Ground wire per phase?

[Johny98]

on the min. wire table is it referring to total amps? I am running 1200 amp with 3x500 MCM per conduit in 3 conduits, is the wire # 3 the min. ground wire for each phase/conduit (400 amp per phase)?

Thx

 

[bob]

on the min. wire table is it referring to total amps? I am running 1200 amp with 3x500 MCM per conduit in 3 conduits, is the wire # 3 the min. ground wire for each phase/conduit (400 amp per phase)?

Thx

#500 kcm 75C is rated at 380 amps, not 400 amps. If you main breaker is 1200 amps you will need to run 3 600 kcm rated at 420 amps. NEC 240.4(C)
does not allow you to round up to the next size breaker. Table 250.122 shows 3/0 copper as the minimum. Where did you get #3?

 

[infinity]

Is this a feeder? For starters 3 sets of 500 Kcmil cannot be used for a 1200 amp feeder. 380 * 3 = 1140 amps. For a parallel feeder each raceway would require an EGC based on the OCPD ahead of the feeder and sized according to 250.122.

 

[SEO]

Also look at section 310.4 (A) thru (E).