Running power to an external building

[123]

I ran a dedicated 15A circuit to our shed. It terminates in a weatherproof dual-gang box containing a light switch and a GFCI outlet. If I do something to trip the GFCI, it can be conveniently reset within the shed. FWIW, for your shed circuit, you plan to tap into an existing indoor GFCI outlet so you'll lose the convenience of accessibility.

 

[beelzerob]

That's a good point. I'm going to have to see what the circuit is on before I decide if I'll go from there or tap into a different one (maybe the garage lights).

But in reality, isn't tripping the breaker a bad thing? I mean, wouldn't it indicate something went wrong, and it's probably something you should fix before hitting the reset and continuing?

Worst case, if I do this as is, the GFCI is on an outdoor outlet about 50 ft away, so it's not as bad as having to go inside and reset it.

 

[123]

If you trip the breaker, you are overloading the circuit (i.e. drawing more current than permitted). Tripping the GFCI device indicates a leakage of current to ground. GFCI detects this condition and disconnects the circuit very quickly to avoid a shock hazard.

You run the risk of encountering this condition if you use electrical equipment outdoors, expecially in wet or damp conditions. If your GFCI "source" is an existing exterior outlet, then it won't be too much of a bother to reset it. Naturally, if the GFCI repeatedly cuts power, then the equipment may need servicing.

FWIW, in my previous home, I had a 220V circuit running 50 feet to a shed and terminating in a circuit-breaker box. The breaker box had three circuits, two for lighting (pool and shed) and another for a pool pump. Having a breaker box in the shed was handy in the event of an overload. For my current home, I simply needed power for lighting and an outlet so I didn't see the need for an in-shed breaker box.

 

[royalj7]

I'm thinking overall probably just having the lights on a switch out at the structure is the best way.

Ummm, this is CocoonTech, where we automate everything, even the stuff that would be easier, cheaper, and less of a hassle without automation. Keep that in mind, you might want to go to MyLifeIsEasierAndIHaveLotsMoreMoney.com if you continue down this path.

--Jamie

 

[beelzerob]

Ummm, this is CocoonTech, where we automate everything, even the stuff that would be easier, cheaper, and less of a hassle without automation. Keep that in mind, you might want to go to MyLifeIsEasierAndIHaveLotsMoreMoney.com if you continue down this path.

--Jamie

Hehehe...an excellent point. And I'll admit I've already considering using one of the controlled ALC switches I got from Sacedog recently...that way I could turn them on from inside the comfort of my house OR from out there. Hmmmm.

Thanks for the helps 123...I'm in the same situation, just wanting to power some lights and an outlet.

 

[klindy]

I'd recommend you run at least #12 wire if you are SURE you'll only have a handful of lights and an outlet or two. If you run that 2" conduit you mentioned you're already somewhat future proofing the situation since you can always pull out whatever wire you're using and use something bigger later if your plans change.

Since you're already digging a trench for the power wire, go to HD/Lowes and buy some 3/4" (or 1") PVC conduit and drop it into the same trench for your LV. Again, with conduit you can always replace the wire if it goes bad or add additional wires for different purposes. The conduit will cost abuot $10-15 (including the sweep elbows to go up out of the trench) so it's worth it.

I don't like digging that much I'd stop at the plumbing aisle and buy some 3/4" water pipe (either PVC or poly or alike) and drop that in the trench too. You can cap it and leave it in the trench or add a hydrant type valve in the shed. You can always attach it in the garage end whenever you decide you need water out there (I'll bet it will happen some day!).

Also, if you have to buy wire, buy THHN wire (perhaps #8 or even #6) and run 2 black wires, a single white wire and a green ground in the 2" conduit. It would be worth the effort now to have the ability to install a 220v circuit, etc. If you do that you will have to run a wire from your electrical panel (hopefully you have 2 spaces left for a breaker because the wire needs to be protected too) and you can connect that to the wires in the trench on the garage wall in a 4x4 (or even smaller) box. On the shed side you can install a small outdoor rated electrical panel (say 6 spaces) or even a 60amp "pool disconnect" which is GFCI already. From those you can run your circuit for lights and a separate one for any outlets. Remember if you install a subpanel in the shed don't bond the neutral bar to the ground bar (that should only be done once on the main panel).

Anyway, worst case, add the smaller conduit for your LV and a water pipe in case you ever decide you need it.

 

[sic0048]

Can water and power be run in the same trench? Is there a minimun distance they have to remain from each other?

 

[123]

Dig a big hole a bury this thing in it. Now your shed has its own power source! Straight out of a 1950's issue of Popular Mechanics ...

 

[beelzerob]

If you run that 2" conduit you mentioned you're already somewhat future proofing the situation since you can always pull out whatever wire you're using and use something bigger later if your plans change.
Since you're already digging a trench for the power wire, go to HD/Lowes and buy some 3/4" (or 1") PVC conduit and drop it into the same trench for your LV.

Done and done. I already had the 2" on hand for the power line, and I had the wife stop by and pick up enough sticks of 3/4" for the low voltage. So I'm set for that now. It's already in the trench and reburied.

But doh!...burying a water line is not a bad idea at all. That would have been a good futureproof idea. However, I see much less likely hood of needing water out there than low voltage...the spigot on the house side isn't too far. Besides, a faucet out there would give me one more to worry about freezing over (since the 2' electrical trench wouldn't be deep enough)

good advice, all. I'll be sure and get that THHN wire, since that has been oft suggested.

 

[klindy]

Can water and power be run in the same trench? Is there a minimun distance they have to remain from each other?

Who besides the 'trencher' would know?

It's a good question and I suppose I can dig out the IRC code book to chcek but I'd have them in the same trench. Of course if asked they were on the "opposite sides of the trench which we dug with a 4' blade on a bulldozer"

 

[klindy]

But doh!...burying a water line is not a bad idea at all. That would have been a good futureproof idea. However, I see much less likely hood of needing water out there than low voltage...the spigot on the house side isn't too far. Besides, a faucet out there would give me one more to worry about freezing over (since the 2' electrical trench wouldn't be deep enough)

If you put a valve in the garage to shut the water off in the winter you'd be fine as long as was one that has the little vent thumb screw on the side - as long at it's installed correctly with the vent down stream from the ball in the valve. In the shed you can use what's called "hyrdant valve" which has the valve at the bottom of a long pipe and a handle/spigot on the top. When you close the valve it drain out the bottom so no water sits in the riser pipe. As I recall, the hydrant valves aren't that expensive (<$40-50) and should be available at your local HD/Lowes.

Unless you're planning on some interesting ice sculptures in the winter months, turning off the water after you get the first hard freeze wont hurt a thing. Still may be better than dragging 40-50' more hose out there when you landscape it! Speaking of....need another zone on the sprinkling system out there? Better get some more PVC!

 

[BraveSirRobbin]

FYI, I'm pretty sure you can only run PVC underground. For surface you should run metal conduit.

 

[SnyperBob]

However, I see much less likely hood of needing water out there than low voltage...t

Outdoor Wetbar FTW! lol

 

[beelzerob]

On a related topic, in case anyone knows this....I've got a 2" conduit coming out of the ground out at the shed. What do I run that into so I can then run it out in separate 3/4" conduit to the lighting fixtures? I guess I'm looking for some kind of gang or junction box that accepts a 2" conduit coming in. I'd have the same issue inside the garage where the 2" conduit comes through the wall. I couldn't find anything at all suitable at Lowes.

 

[klindy]

On a related topic, in case anyone knows this....I've got a 2" conduit coming out of the ground out at the shed. What do I run that into so I can then run it out in separate 3/4" conduit to the lighting fixtures? I guess I'm looking for some kind of gang or junction box that accepts a 2" conduit coming in. I'd have the same issue inside the garage where the 2" conduit comes through the wall. I couldn't find anything at all suitable at Lowes.

Lowes/HD have PVC boxes (with covers) that have no holes in them. Get a 2" connector (the one with male threads on one end and a slip connection on the other). You'll need a 2" connector nut (they come is packages of 2). Get a hole saw that's the same size as the connector and drill the box wherever it's convenient so that you can mount the box properly. I suspect the pipe will be coming into the bottom of the box.

Did you use a 2" 90 bend on the bottom of the trench?

You can drill holes for the 3/4" conduit the same way wherever it's convenient on the sides of the box.

The box cover has a rubber gasket (looks like an O-ring actually) that will make the box weather tight.