400 AMP Service

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Jimmy7

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Location
Boston, MA
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Electrician
I have a 400 amp underground service to do for residential home. I’m curious what others run for underground service conductors. I thought I could use 310.12(A) for the service conductors. Can I parallel the conductors in 310.12(A)? Could I run two sets of 3 - 2/0 copper in 2” pvc, or two sets of 3 - 4/0 aluminum in 2” PVC?

Thanks,
 
Assuming some portion of your PVC will need to be Sch 80, you may well be out of choices with 2" for a 400 amp
 
Power Company probably has minimum size requirements for conduit. For instance, Evergy requires minimum 3-inch no matter what size service - even 100 amp
 
If these conductors are serving multiple service disconnects, then you can size them to the load calc, not necessarily the whole 400A. 2 sets of 4/0 AL each in 2" is an option. With the price of PVC still pretty high, I would consider using 4" SDR 35 sewer pipe and two sets of 4/0 USE-2 conductors. In that case there would be some derating due to the 4CCC, but probably still fine.
 
James L said:
Power Company probably has minimum size requirements for conduit. For instance, Evergy requires minimum 3-inch no matter what size service - even 100 amp
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I always hear such things and I find it fascinating. Why does POCO have a say in conduit on the customer side of the service point? Are they installing the conductors? Or is this on the utility side of the service point?
 
electrofelon said:
I always hear such things and I find it fascinating. Why does POCO have a say in conduit on the customer side of the service point? Are they installing the conductors? Or is this on the utility side of the service point?
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Residential underground, POCO supplies conductors to meter.
 
electrofelon said:
But you have to supply the conduit run? Service point at the meter line lugs?
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Yes, for Evergy.

Platt-Clay requires a conduit stubbed down 18 inches into the ground, and they provide direct burial cable. I've only done one service in their area since 1999, a 320a 2 years ago with 3-inch stub. I don't know if smaller service can have smaller conduit stub.

BPU (KC,Ks) same as Evergy for 320a but I'm thinking they may allow 2-inch for 100a and 200a

IPL (Indep.,Mo) have their own rules, too, which I'm not sure

They all supply the wire/cable
 
Our local EMC you only supply the conduit out of the meter to below grade, they bury triplex from there to the transformer. I did one in Tennessee, Volunteer Electric, they wanted a conduit from the meter to the transformer, and no more than two 90’s. If you needed more, you stubbed up into a pull box, but they pulled the wire. In parts of Ohio, they will not run underground, your service is at the road, and you install it from there to the house.
 
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I'm so glad it's different around here and we don't have to deal with any POCO spec'd conduit run nonsense. They are always the biggest wimps I've ever seen. They want like 12" conduit, no more than 5 degrees of bends, 18,000 lb pull tape, pull boxes every 35 feet, 47 gallons of pulling lubricant, and the list goes on and on...🙄
 
electrofelon said:
I'm so glad it's different around here and we don't have to deal with any POCO spec'd conduit run nonsense. They are always the biggest wimps I've ever seen. They want like 12" conduit, no more than 5 degrees of bends, 18,000 lb pull tape, pull boxes every 35 feet, 47 gallons of pulling lubricant, and the list goes on and on...🙄
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Forgot the swedge couplings and no bell ends
 
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