Electric to a Shed, What Do You Think Of My Plan??

[Tom_From_NJ]

I have a shed I want to run power out to. I will not have any high power needs, i.e. welding, etc.. I plan to run 200 feet (from the house breaker box to the shed) of 10/3 from a single 20 amp breaker. On one circuit, I will have 2 inside outlet plugs, one on each side of the shed, both on a GFI. On the other circuit, I will add 2 outside 500 W lights, and 4-100w lights inside. I will run the wire in PVC ,12 inches down; the wire will be direct burial type. I will run all wire, 14/2, in the shed inside of PVC conduit to protect it from the mice. I will run phone cable outside of the conduit, at the bottom of the conduit.

Questions

If I use schedule 80 threaded conduit pipe, can I only go 6 inches down?

What size conduit should I use with 10/3, 1 inch?

Will this set up work?

Thanks for your help. [img]/forums/images/icons/confused.gif[/img]

Tom

[Inspector507]

Sounds like most of your plan is okay Tom. However the correct burial depth for PVC is 18". Rigid Metal Conduit can be buried at 6".

[WVBill]

</font><blockquote><font class="small">In reply to:</font><hr />
...run 200 feet of 10/3 from a single 20 amp breaker. On one circuit, .... On the other circuit, ...

[/ QUOTE ]
I'm not following how you get two circuits from a single 20 amp breaker. [img]/forums/images/icons/confused.gif[/img]

[EJB]

&gt;&gt;I will not have any high power needs,

I am not an expert on these things, but I'd really make sure you plan enough for the future and weigh the potential of wanting have some "high power" needs down the road and figure out what the extra cost would be to plan for it now...maybe it wouldn't be significant either way (i.e. wire for it now, or dig it up and do it again later), but if it was me, and the incremental cost of having extra power available down the road was not significant, I would do the etra cost now if budget allows.

On the other hand, if you knew for sure there was very little possibility of needing it, than your plan is probably better...

...I do know that if you hang around here too long, sooner or later we are going to talk you into getting a welding machine.... [img]/forums/images/icons/laugh.gif[/img]

[mushrock]

You just got some good advise from EJB.

Will your plan work for what you discribe? Yes.
Will it work if your needs expand? maybe, depending on how much you add.

Here are some suggestions:

If you use the 10/3, and I assume you are intending to hook it to a 240 circuit breaker so you will actually have two 120 volt lines in the shed. Why don't you install a 100 amp breaker box in the shed- much more than is needed for your current plans but, check the prices, you will find that they are inexpensive and you can always add more breakers later. NOTE: if you decide to go this route check the cost of additional breakers before you buy the circuit breaker box. Some manufacturers give you a deal on the circiut breaker box with a few circuit breakers in it and then really hose you when you try to buy additional circuit breakers to fit the box.

Instead of using PVC conduit in the ground think about using black PVC water pipe. It comes in 100', 200', and I think I've seen 500' rolls and it is inexpensive. In addition to the cost, one of the main advantages is the fact that there would be NO connections under ground. I ran a line to my shop last spring and used a 3" pipe (I had a lot to put in it, 2 #2 Cables, a #4 ground cable, air hose, phone lines, intercom lines, strings for future cable/wire "pulls". Everything that goes in the pipe will have to be pushed/pulled from one end of the pipe to the other so make sure you get a large enough pipe). The pipe is fairly stiff but will easily make moderate bends. For bends like 90 degrees you just need to heat it up with a propane torch, bend it and wait for it to cool ...er you do slide the cable(s) into the pipe before you put any 90 degree bends in it. I did this last spring when I ran a new line from my garage to my workshop. I ran the pipe under the walls, cut a hole in the concerte floors and have the ends of the pipe sticking up inside of the garage and workshop about two feet above the floor. After the wire connections were made the ends of the pipe were sealed with a foam insulation to keep the critters out.

Note: Once it's underground you may know where the cable is but no one else will know. Draw a simple diagram and explaination and hang it near the circuit breaker box so the next owner will know. Also, when the pipe is in the ground prior to burying it, use a can of RED spray paint and walk along the trench spraying the pipe so future excavators who may dig in that area will see that this is NOT a water line if they happen to dig it up. Red spay paint is a recoginized danger sign for buried pipes. You do not need to paint the whole pipe red, just stripe it as a warning, with 200' of pipe it shouldn't take a whole can of paint.

One last thing, I really would use a larger cable, two runs of single conductor and a copper gound cable - usually one size smaller. Check the cost compared to a muliti-connductor cable. Also, I would/did drive a ground rod down outside the shop and tied on to it just to be sure.

[Inspector507]

mushrock,
The black PVC water line does not meet the requirements of The NEC®. He really needs to use the properly listed/labeled materials [img]/forums/images/icons/grin.gif[/img] .
Driving a ground rod at the shed/barn/garage is necessary in SOME cases, but not always.

[StanleyinMd]

&gt;&gt;&gt;Note: Once it's underground you may know where the cable is but no one else will know. Draw a simple diagram and explaination and hang it near the circuit breaker box so the next owner will know.&lt;&lt;&lt;

What I also do is take photos of everything that goes underground. This includes cable tv line, t/p, water, electric, gas, etc. On the back of the photos I then draw my measurements to the house, a tree, next to the blacktop, next to the fence, outbuilding, etc. Even though the tree might get cut down or die at least you have some reference points rather than none.

[Phred]

tom,

I posted some coments over on TBN about this issue.

I would add to watch the number of 90s you have underground. These add a lot of resistance to pulling. Also I find the PVC is a lot easier to pull through than rigid or EMT. The surface of the PVC is smooth so it creates less friction.

Fred

[bgott]

You aren't supposed to have more than 360 degrees of bends. When I do underground cable I cheat. I lay out the cable and the conduit by the trench and slide the conduit over the cable. I glue it as I go and then I chunk the whole mess in the trench and bury it. The electrician I worked for didn't really like it but I could do the job myself that way, I didn't need someone on the other end feeding the cable. I'm 6'4'' and 235# so I always get stuck with the pullin' and never get to do the feeding. [img]/forums/images/icons/mad.gif[/img]

[Tom_From_NJ]

Ok after some feed back on my idea I have made the following changes:

I will use one inch rigid conduit and bury it 6 inches. I do not have to incur the cost of a ditch witch for a few hours and my lawn does not get totally messed up. I will have one straight run with only 2-90 on each end. I will also add plastic CAUTION tape on top of the conduit before I back fill and take pictures and measurements and attached it to the breaker box for the next guy to own the house.

I will use 2-20 amp single pole breakers.

I will bury the phone line in a separate PVC pipe.

I will look at the cost difference of 8 vs., 10 gauge wire.

Thanks for the comments it has helped me refine the
project. [img]/forums/images/icons/grin.gif[/img]

Tom