Electrical Service to Shed

[rroberts]

Hey all! Need some guidance on wiring project...

I have a small shed approx 250ft from service pole. I am planning on running power from pole to shed for 30amp/240v service. I would like to bury wire in a trench inside of plastic conduit for ease of replacement or upgrate later on.

OK Now, what would be the proper wire (and cheapest) I would need to do this?

I know I will need two hot wires and a neutral but will I need to also run a ground back to the pole or will grounding at shed be sufficient?

Is THHN the best wire to use?

Also, What size conduit would be proper?

Thanks Guys

 

[p_mori7]

Is the shed the only building on the property ?

Might there be another building with power closer to the shed ? That would make it easier to run power to the shed.

Total run will need to be taken into account for wire sizing.

 

[pattenp]

What kind of connection will be made at the pole? Is there a meter with a breaker panel?

 

[Roots]

You might want to contact your utility or AHJ about what their requirements are to tap into... This might not be a job which a home owner is even allowed to do.

 

[pattenp]

I can tell you for 30A at 250', I would most likely pull at least #6 aluminum XHHW-2 using at least 1" PVC conduit. I'm assuming this will be a branch feed from a service panel at the pole so you will need 4 conductors. If I was running conduit thinking I may increase the power in the future I would probably use 2" PVC.

Edit: Actually #4 aluminum for 30A at 250' would be better.

*

 

[tylernt]

I believe buried conduit is considered a wet location by the NEC, hence pattenp's suggestion of XHHW instead of THHN.

Whatever size conduit you determine that you need, I'd go up a size or two from there to allow for future expansion and to make pulling easier.

 

[pattenp]

I believe buried conduit is considered a wet location by the NEC, hence pattenp's suggestion of XHHW instead of THHN.

Whatever size conduit you determine that you need, I'd go up a size or two from there to allow for future expansion and to make pulling easier.

Actually most if not all THHN wire is also THWN rated which is for wet locations. I just suggested XHHW because that's common on aluminum. And conduit underground is considered a wet location.

 

[rroberts]

Is the shed the only building on the property ?

Might there be another building with power closer to the shed ? That would make it easier to run power to the shed.

Total run will need to be taken into account for wire sizing.

I have a house but the pole would be closer.

What kind of connection will be made at the pole? Is there a meter with a breaker panel?

Yes, meter with disconnect box. I will install a outdoor subpanel to run the feed.

You might want to contact your utility or AHJ about what their requirements are to tap into... This might not be a job which a home owner is even allowed to do.

I live out in the country. It will be no problem with my electric cooperative.

 

[joe_padavano]

Conduit size depends on what your planned upgrade will be. Installing conduit sized for the current 30A wire is worthless because you can't run anything larger in it. 100A service will require 1.5" conduit, 200A needs 2" minimum. Frankly, you might be better off just buying larger USE direct burial cable now and not using conduit. You can always run 30A on larger wire than needed (though we might need another four page thread to debate that... ) and simply increase the circuit to the max allowed amperage of the wire at a later time.

 

[pattenp]

Be aware, USE type wire is not allowed by NEC to be run inside of the structure. You would need to transition to a wire type with fire retardant insulation such as THHN/THWN or RHH-RHW or XHHW in a junction box on the outside of the building.

 

[joe_padavano]

Be aware, USE type wire is not allowed by NEC to be run inside of the structure. You would need to transition to a wire type with fire retardant insulation such as THHN/THWN or RHH-RHW or XHHW in a junction box on the outside of the building.

OK, to clarify, use USE-2/RHH/RHW-2, which is about all one can buy easily around here when you ask for USE type wire. The 2-2-2-4 version of this is readily available at Home Depot, Lowes, and others. Even electrical supply houses sell the USE-2/RHH/RHW-2 rated wire.

 

[pattenp]

OK, to clarify, use USE-2/RHH/RHW-2, which is about all one can buy easily around here when you ask for USE type wire. The 2-2-2-4 version of this is readily available at Home Depot, Lowes, and others. Even electrical supply houses sell the USE-2/RHH/RHW-2 rated wire.

The USE-2/RHH/RHW-2 that HD and Lowes sells is called Mobile Home Feeder. Lowes and HD also sell URD which is only USE-2. I've seen a fair amount of people on this site buy the URD thinking it can be run inside the building.

 

[James-W]

I am completely confused. From reading over the posts in this thread I gather that you have a pole with a meter on it and you want to run power from the pole to the shed. Is that correct? Meters are generally mounted on the house, not on a pole, so if that is what you have it is a new one on me.

 

[wyliesdiesels]

I am completely confused. From reading over the posts in this thread I gather that you have a pole with a meter on it and you want to run power from the pole to the shed. Is that correct? Meters are generally mounted on the house, not on a pole, so if that is what you have it is a new one on me.

Is most definitely new to u as ive done work on meter mains mounted to poles in the countryside all the time!