Grounding Electrode Conductor?Size

[Pistu]

250.122 Grounding Electrode Conductor?Size.


Question: What size grounding electrode conductor and how many is required for a 800A breaker that is supplied with

three pvc conduit of 350 kcmil conductors per phase
four pvc conduit of 4/0 kcmil conductors per phase
and etc

to MCC?

Plus, 4/0 Awg underground wire added.

Pistu Papp

 

[Dennis Alwon]

250.122 Grounding Electrode Conductor?Size.


Question: What size grounding electrode conductor and how many is required for a 800A breaker that is supplied with

three pvc conduit of 350 kcmil conductors per phase
four pvc conduit of 4/0 kcmil conductors per phase
and etc

to MCC?

Plus, 4/0 Awg underground wire added.

Pistu Papp

250.122 is for equipment grounding conductor. Look in 250.66 and see if that helps

 

[iwire]

First thing is you have got to get the terminology right.

250.122 is about the Equipment Grounding Conductor.

250.66 is about the Grounding Electrode Conductor.


Also are you talking about a service or a feeder?

 

[infinity]

Since it's unlikely that an MCC would be used as a service I would say that these conductors are feeders. Therefore you would use table 250.122. For a 1200 amp feeder that would be a #3/0 cu conductor in each raceway whether you used 3 or 4 conduits based on the 1200 amp OCPD protecting the feeder.