Grounding

[jim123]

I'm coming from a three phase 600 amp switch gear breaker to a distribution panel .Then from there I'm mounting a three phases 150 amp panel . My question is does the ground coming from the switch gear to the distribution panel have to be bounded to the neutral or be separate. I'm thinking this is a sub and the switch gear would be my main . Thanks for ur help

 

[Ponchik]

Generally, the neutral bonds to the grounding only at the service.

 

[rlundsrud]

From your description, these are not separately derived sources (SDS), so no, you would not bond the neutral. You would also need a separate ground bar in the sub panel as you can't land your EGC wires at the neutral bar.