GEC for parallel conductors

[aelec84]

forum,

I have (2) parallel sets of 400kCMIL copper conductors and the GEC is connected to common ground bus and it is extending it to other electrodes. I believe equivalent area has to be considered which would be 800 kCMIL requiring 2/0 gec. Is this right? Thanks,

 

[augie47]

Correct

 

[aelec84]

Per 2023 NEC, Table 250.66, Note 2 is confusing. What does that mean and when does it apply?

 

[infinity]

Per 2023 NEC, Table 250.66, Note 2 is confusing. What does that mean and when does it apply?

Note 2 is not applicable to your installation. If you had a sub-panel in a remote structure there would be no service conductors. In your scenario 2*400 kcmil=800 kcmil, from 250.66 that would be as you've stated correctly a #2/0 GEC.

 

[aelec84]

Note 2 is not applicable to your installation. If you had a sub-panel in a remote structure there would be no service conductors. In your scenario 2*400 kcmil=800 kcmil, from 250.66 that would be as you've stated correctly a #2/0 GEC.

Thank you. To clarify these are not service-entrance conductors. The feeders are from separately derived system.

 

[infinity]

Thank you. To clarify these are not service-entrance conductors. The feeders are from separately derived system.

Thanks for clarifying. The OP sounded like a service but the #2/0 would be the same for the SDS.