ECN Forum Forums General Topics of the Trade General Discussion Area What changed, the wire or the breaker?

So... for a 3-Phase 240/120 Delta system. On a 400A, 600A & 800A service, what size conductors would be necessary. Each set paralleled in seperate conduits, using the largest size and the fewest parallels as practical.

I always used one set of 500 for 400A and two sets of 500 for 800A and the inspector passed it. Was this wrong?

I don't believe I have ever done a 600A service but I'm designing a job that someone else is intending to use paralleled 500's for a 600A service. I was told that the paralleled 500's would not give me 800A.

Who's right?

Thanks for all of the replies and good discussion.