[Johnnoh]

The shed is not in yet, but I'm starting to think about how I'm going to wire it before the slab goes down next week.

The load requirements will be minimal, but I would like to have breakers so I can cut power to the receptacles and outside/ inside lighting from the shed. I probably won't run any heavy power tools - maybe a shop-vac or circular saw once in awhile. There will be inside lighting and one motion controlled spotlight. I was considering a 12/3 w/ ground run from a 20A double pole breaker to a small subpannel in the shed (120 feet). There will be PVC conduit up through the slab with #12 THHN.

Does this sound like overkill? Any suggestions?

Thanks,

Jon

 

[220/221]

Underkill.

I believe it's a 30 amp minimum for a sub panel.

You can run two 20 amp circuits if you want.

I'd run 10's in 3/4 or 1 inch conduit. You can pull larger wire in the future if you need to upgrage to a 50 amp sub.

 

[mpoulton]

I agree, definitely underkill. You have the once-in-a-lifetime opportunity now to save yourself a bunch of time and money later by installing an adequate service for your shed. :thumbsup: You may not think you want to run any serious equipment, but if you don't plan for it now you won't be able to change your mind later. The most expensive part of this kind of installation is digging the trench to bury the conduit - the additional cost to use a #6 or #4 (Al) feeder instead of #8 UF cable will not be a big hit on the project. If it were my shed, I would install a 50 or 60A minimum feeder. Even that is small if you decide you want a compressor or welder in the future.

 

[Scuba_Dave]

You can run (1) circuit to the shed
OR
You can run (1) MWBC circuit to the shed - 2 circuits on a double pole breaker sharing the neutral
OR
You can run feeders to the shed to power a sub-panel

How big is the shed?
How far will you have to run power?
Any chance of a hot tub/pool anywhere near the shed?

I ran #6 feeders to the shed for a 60a sub
I have a pool pump out there, lights, plenty iof circuits

Make sure the PVC conduit is large enough to carry larger wire just in case
Min size I woudl run is 1"
I also ran 2 spare conduits to the shed in case I ever want a phone line, LAN or TV out there

 

[J. V.]

Underkill.

I believe it's a 30 amp minimum for a sub panel.

You can run two 20 amp circuits if you want.

I'd run 10's in 3/4 or 1 inch conduit. You can pull larger wire in the future if you need to upgrage to a 50 amp sub.

60 amp.

 

[jbfan]

Underkill.

I believe it's a 30 amp minimum for a sub panel.

You can run two 20 amp circuits if you want.

I'd run 10's in 3/4 or 1 inch conduit. You can pull larger wire in the future if you need to upgrage to a 50 amp sub.

You can run any size sub panel you want, but requires a min. 60 service rated disconnect.

 

[Johnnoh]

So if I decide to go with the 20A MWBC - what is the procedure to share or branch off to the (2) circuits? I didn't want to go the feeder route with grounding rods. My garage is only 60' from the shed - that's where my compressor and welder are. The shed is only 10'x12' and will be mostly used for storage.

Jon

 

[Scuba_Dave]

You bring the wires into the shed - junction/outlet box
Then branch off from there to each circuit as needed
Pigtail to the common neutral for each circuit

Under NEC 2008 you now need a double pole breaker
Two single poles are not an option

I would make sure that the conduit is beig enough to pull bigger wire in case you ever want to upgrade

 

[zpm]

And you need a disconnect at the shed.

 

[vsheetz]

I would ensure a ufer ground gets installed before pouring the concrete.

Here is a good deal on a subpanel all set for a garage or workshop.
http://www.lowes.com/lowes/lkn?action=productDetail&productId=214802-76863-TM1210CCUG1K

 

[J. V.]

I would ensure a ufer ground gets installed before pouring the concrete.

Here is a good deal on a subpanel all set for a garage or workshop.
http://www.lowes.com/lowes/lkn?action=productDetail&productId=214802-76863-TM1210CCUG1K

Great price, decent panel. I would buy it.

 

[drthornton]

Been There

I just finished a very similar upgrade in my backyard. I built a shed last summer but did not put Electric in it. This year we were given a Hot Tub requiring 50 Amp GFI. I got quotes on doing the electric and even considered doing it myself. I need about 140ft of trench dug which in my part of North Texas is very difficult(Clay soil). I got 3 quotes and 3 different ideas and ended up getting a 125Amp, 20 slot, subpanel placed on the outside of my shed then ran the 50Amp GFI to the tub and 2 110/20Amp to an external box right next to my patio. He also oversized the conduit for future circuit pulls and left a pull string in the conduit. I am now set for anything I could ever need for my backyard and shed. I am finally going to wire my shed and I don't have to worry about any constraints. Cost was $1700 but was worth it.

My point is 2 fold.
1. Get the most you can possibly afford you will be glad you did in the future. Put in bigger conduit than you think you need.
2. Use a contractor if you are not experieinced and get multiple quotes. My quotes were $1500 difference between the highest and lowest. Now this is not to say just go with the cheapest. You should get a good feel from your contractor and ask for references. Also note that I added up all the costs for what I hired done and could not have done it myself for as cheap as I had it done.