Outside: Adding an outlet to a switched light fixture

indigo

Ok, so here's what I've got:

On the back deck I've currently got a single switched outdoor light socket mounted on the side of the house. So it's a junction box then lampholder mounted on the brick wall.

I'd like to add an outlet by running conduit down to about outlet height (is there code here? will 12" above the deck or so do? it'll be like a 3-4' run total) Then mount another junction box and put the outlet in there. Straightforward enough -- the switch will turn on both the light (a par38 cfl flood) and the outlet

Here are my questions:
-Do I need a GFCI outlet? I assume absolutely since it's outside.
-What do I do for the ground on the outlet? Just ground it to the box that's mounted to the brick wall? Is there a better way to do this?
-I believe that there is no ground going to the flood box so do I just add a positive and neutral on and send that down the conduit? Dealing with the grounding in the other outlet jb?
-Any thing special to note about the conduit?

Thanks so much!

teamo

You can run the conduit down from the existing light. 12" is fine for the height. You need to use a GFCI outlet. Is this an old circuit without a ground? If it is you cannot extent it. Is there a ground wire in the existing box? Is there currently conduit running to the existing light? If so then the conduit might be the grounding conductor (assuming that it is metal). If you don't see a ground wire in the box then disconnect the light and test for power between the hot and the metal of the box with a voltage tester. If you have voltage between the hot and the metal box then most likely you have a ground. You can use metal conduit to carry the ground but it is better to pull a seperate grounding conductor. Use an outdoor box for the outlet and also compression fittings for the conduit. If you use plastic conduit then you must use a seperate grounding conductor.

secutanudu

If this circuit is already protected by a GFCI circuit earlier in the run, you do not need the outside one to be GFCI.

Whether you do GFCI or standard outlet, make sure it's weather resistant:

GFCI: http://www.amazon.com/Leviton-R52-W7899-TKW-Smartlock-Resistant-Receptacle/dp/B002KHXIFK/ref=sr_1_1?ie=UTF8&s=hi&qid=1260806892&sr=8-1

Non-GFCI: http://www.leviton.com/OA_HTML/ibeCC...minisite=10026

You should also get an in-use cover, so that if you leave something plugged in for an extended period of time, you are still protected:
http://www.amazon.com/Taymac-MX3200-...0806928&sr=1-4

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Andrew

indigo

Got a chance to crack the box open again -- from what I can tell there are only two leads and they popout of the wall and into the box through some sort of plastic bushing. I guess it was just always intended to be a light and so they didn't run a ground to it (the electric was completely 100% redone in the early 80s for whatever that is worth)

Am I out of luck then?

Also the box doesn't have a conduit ring on the bottom, but that's not too big a deal either way.

Thanks!

This is more or less what the fixture is:
http://www.tradevv.com/TradevvImage/...ght-A4c95b.jpg

Except for a rectangular JB and only a single holder.

secutanudu

Are you sure the j-box itself is not grounded? Is there a grounding wire from the fixture to the box?

If you are missing a ground on that part of the circuit...I am not sure if it is up to code to extend the circuit. But you CAN use (as far as I know) a 3-prong GFCI outlet on a non-grounded circuit (since the GFCI itself provides ground fault protection). So I would think it's ok to pigtail off the black/white wires in your lighting J-box, extend wires in the conduit (use THWN since it's outdoors) to another single-gang outdoor box with a weather-resistant GFCI outlet. If you want to stay up to code, then this all hinges on it being legal to extend an ungrounded circuit, assuming yours is not grounded.

Keep in mind that with this setup, the light switch will have to be ON for the outlet to work. This may be something to think about if you plan to put up holiday lights using this outlet. Might not be an issue if this light switch is always on and you use a motion sensor to turn the fixture on/off.

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Andrew

indigo

There does not appear to be anything in that box except the 2 wires -- the fixture is just a really simple 2 wire that I just replaced a few months ago.

It's strange that it would be ungrounded though -- hmmm... what you're saying about the GFCI does make sense though.

Yeah, it being on a switch is kind of annoying, but I guess if it gets too annoying I can always cap of the light fixture and just have the outlet on a switch or put in a motion sensor light or whatever sensor it is that only turns on at night.

Anyone else have thoughts on this?

secutanudu

How difficult would it be to run new wire to this fixture? You could tap into a grounded circuit and avoid this whole confusion. And if so, you can run an extra set of wires to go to your outlet, so the outlet wouldn't be switched.

Since the lighting box is mounted to your house, you can run romex into the back of the box (still considered indoors). Once the wire leaves the box and goes into conduit that runs to your outlet, you have to switch to THWN wire. Most THHN wire is also rated for THWN, so just look at the wire itself in home depot or wherever, it will mostly say THHN/THWN.

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Andrew

indigo

To put it mildly it would suck. It's the brick exterior on a 110 year old house with god knows what between it and the drywall on the other side. This is up on the 2nd floor too which has it's own panel so the wire probably doesn't go too far, but it would really be a bear to get to it without gutting that wall and is more than the "easy" fix I was looking for.

Maybe on weds I will pop the box off the house and rummage around in the hole in the brick -- maybe they cut the grounding line way back.

j. pierce

Helpful this thread came up - two questions I had were just answered. You folks are helpful here!

I'd check at the switch first. At least, that seems easier and tells you whether it's worth poking in the brick for a missing ground wire.

secutanudu

You can do this with a timer switch or a dusk-to-dawn sensor that goes between the bulb and the fixture.

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Andrew