100A Service to Shop

[Smiles79]

Power from the street comes to a pole on my property, through a pole-top disconnect, then to the house. Folks here recommended the best way for me to get power to my shop would be to splice into the load side of the pole-top disconnect. Power company says I have 200A service to the house (150A panel in the house) and can send 100A to the shop.

What size/type of wire do I need to be able to provide a full 100A to the shop? I know A lot of folks use 2-2-2-4 MHF and a 90A breaker, but I'd like the full 100A unless it's significantly more expensive.

Edit: The wire run will probably be around 150ft.

 

[Bert_]

#1 is 100A but you might not find it it direct bury. 1/0 is the next size larger and is common

 

[wyliesdiesels]

OP didnt say anything about direct bury

I would just bury some conduit and use individual conductors of #1 AL xhhw with a #6 AL for EGC.

 

[Smiles79]

OP didnt say anything about direct bury

I would just bury some conduit and use individual conductors of #1 AL xhhw with a #6 AL for EGC.

Thanks! So that will allow me to feed 100A instead of 90? And I can use xhhw for the whole run as long as it's in conduit?

Looks like it's about $0.12/ft more expensive than MHF on wireandcableyourway. Only $18 over the whole run. Worth it!

 

[mm08822]

You could reduce the neutral conductor to #3. (if your local codes permit.)

 

[Norcal]

Thanks! So that will allow me to feed 100A instead of 90? And I can use xhhw for the whole run as long as it's in conduit?

Looks like it's about $0.12/ft more expensive than MHF on wireandcableyourway. Only $18 over the whole run. Worth it!

PVC conduit is no longer cheap like it was in the past, but pipe is always better then direct burial, conduit is a one time insurance policy.

 

[mike93lx]

Thanks! So that will allow me to feed 100A instead of 90? And I can use xhhw for the whole run as long as it's in conduit?

Looks like it's about $0.12/ft more expensive than MHF on wireandcableyourway. Only $18 over the whole run. Worth it!

Yes, 100a is good with #1.

If you really expect to pull 100a, you should go up a a size as voltage drop will be a factor at that distance

 

[Smiles79]

Yes, 100a is good with #1.

If you really expect to pull 100a, you should go up a a size as voltage drop will be a factor at that distance

Yeah, it looks like 1/0 would be the proper size. What size does the egc need to be?

 

[mike93lx]

Yeah, it looks like 1/0 would be the proper size. What size does the egc need to be?

I believe #4. You can use #1 for a neutral.

This is where scope creep costs money. Most single person shops are fine with a 60a feed, which #2 can do easily at that distance

 

[luvtheheat]

You could reduce the neutral conductor to #3. (if your local codes permit.)

I thought neutral carried same amount of amperage as the hots, just back to the source.....?

 

[Bert_]

I thought neutral carried same amount of amperage as the hots, just back to the source.....?

In 120/240 single phase the neutral carries the imbalance. If you have 30 amps on phase a, and 20 amps on phase b, the neutral will carry 10 amps.

It's almost impossible to put 100 amps on the neutral of 100 amp feeder.

 

[PCustoms]

Looks like it's about $0.12/ft more expensive than MHF on wireandcableyourway. Only $18 over the whole run. Worth it!

Check your local supply houses. As a walk up customer mine just came in lower then that site, even lower once shipping was factored in.