1200A Service from transformer to main switch

Sqjlighting

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Location
Henderson NV
Occupation
Electrical
If I’m running 400ft underground from transformer to 1200A 208/120V 3 Ph 4 W main switchgear, please confirm 4-3” pvc Conduits with 1-500 kcmil and 1-#3/0 ground wire in each? Las Vegas location.
 
380*4=1520 so the wire size is good. That should be 4-500's per raceway. Is this ahead of the service disconnect? If so then there should not be an EGC in any of the raceways.

Welcome to the Forum. :)
 
As Rob said, we need confirmation on customer or utility transformer. If this is a service there would be no EGC. If this is an SDS and it is outside and PVC then I would think you would use the exception where you can Bond both ends, so no ssbj needed
 
You can play with the numbers but most likely you could drop a wire size without an excessive voltage drop.
(For example a set of 400 kcmil would only give you 3% VD at 1100 amps)
 
380*4=1520 so the wire size is good. That should be 4-500's per raceway. Is this ahead of the service disconnect? If so then there should not be an EGC in any of the raceways.

Welcome to the Forum. :)
Except for in Arkansas, for some reason (probably uneducated inspector) they want a EGC from the transformer to the service disconnect! LOL!
 
If I’m running 400ft underground from transformer to 1200A 208/120V 3 Ph 4 W main switchgear, please confirm 4-3” pvc Conduits with 1-500 kcmil and 1-#3/0 ground wire in each? Las Vegas location.

I see you do not mention CU or Al , Thwn or Xhhw etc.
Is you PVC sch 40 all the way. No sch 80 anywhere.
Also if you add the EGC ( 3/0 cu) for some reason, check your raceway fill.

400 foot run in 3" kinda tight depending on raceway routing and bends.

4-500 & 1-3/0 in. 3" sch 40 PVC per NEC is over 40% fill.
 

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I would like to add if a compact Xhhw for the 500 and a Thwn 3/0 is used it is under 40% fill and code compliant for sch 40 PVC.
 

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