Parallel feeds

[infinity]

That's what I thought at first but I think he means six conduits with one set per.

I think that you're correct, I read it as 6 conductors per conduit.
I would add two conduits and use 600 kcmil.

 

[winnie]

If you have 9x 300 kcmil per phase (3 of each phase in 3 conduits), then depending upon the neutral requirements you might be able to fit 2000A in the existing 3 conduits.

If you can get compact stranded Cu even better.


Jon

 

[Dvdclntlrsn]

Shouldn’t the ground be sized to the individual raceways since each raceway has three 600mcm with a neutral thus a #2 copper

 

[Dvdclntlrsn]

I like the suggestion of nine 300mcms but was told I’d have to derate it and that would be 70%

 

[Dvdclntlrsn]

Ok I like the suggestion of nine 300 mcm conductors but was told I’d have derate it and would be 70%

 

[infinity]

I like the suggestion of nine 300mcms but was told I’d have to derate it and that would be 70%

Yes 9 CCC's would require the 300's to be derated to 70%.

 

[david luchini]

Shouldn’t the ground be sized to the individual raceways since each raceway has three 600mcm with a neutral thus a #2 copper

Full size ground is required in each conduit, as mentioned earlier. Per 250.122.

 

[qcroanoke]

All this is for a casino sign running continues

This is a casino sign feed?
There should be a P.E designing this. Jmo

 

[winnie]

Yes 9 CCC's would require the 300's to be derated to 70%.

Ampacity of a single copper 300 is 320A. (This is the 90C ampacity, and if you use 90C conductors you can use that for derating).

9 * 320 * 0.7 = 2016

Jon

 

[infinity]

Ampacity of a single copper 300 is 320A. (This is the 90C ampacity, and if you use 90C conductors you can use that for derating).

9 * 320 * 0.7 = 2016

Jon

I didn't check the conduit fill but for 2000 amps the 300's would work.

 

[electrofelon]

This is a casino sign feed?
There should be a P.E designing this. Jmo

I don't see any need for a PE for this, probably just an actual Electrician.

 

[winnie]

I didn't check the conduit fill but for 2000 amps the 300's would work.

9 300's would fit, depending on conduit type.

The problem is if there remains sufficient room for EGC and neutral.

If the conduits were existing and changing them a major cost, then I'd try to get compact stranded Cu.

If this were initial design and conduit being selected then I would go with more conduits.

Jon

 

[Dennis Alwon]

Shouldn’t the ground be sized to the individual raceways since each raceway has three 600mcm with a neutral thus a #2 copper

The equipment grounding conductor must be large enough to trip the overcurrent protective device. There is a reason that a 250 kcm conductor is required for 2000 amp overcurrent protective device. Each conduit must be capable of tripping that 2000 amp breaker.

 

[djd]

Ok I calculated at 90 and not 75. So if I go 400 mcm copper do you see a problem

I didn`t know there was 400 mcm

 

[kwired]

I didn`t know there was 400 mcm

It is in ampacity tables in NEC, though it may not be all that commonly used.