What happens if one uses regular housing wiring romex and bury it underground to a light post? I'm working on my front driveway lights. I am making new foundations for them and I find the wire from my house to the one lamp post is UF. The wire going from that post to the second post about 50 feet away is regular romex. Stripping the insulation back on the UF reveals clean copper wire. Stripping the wire back on the romex buried underground and I find the surface of that copper wire has some moisture corrosion/patina. So what happens if I continue to use this romex buried under the ground? A slight bleed off of electricity to the earth and the ground wire? Maybe none? It has been underground for 20 years now. The corrosion/patina is not that much in my opinion. Probably caused by just a little moisture getting thru the vinyl covering. I can run a new UF wire but that is a bit of work. If leaving the romex is no big deal I would rather leave it. It has worked for 20 years now. The white covering still looks new.

Thanks
Rodney

The paper in Romex is the key. It will cause the copper wire to fail by taking in moisture and rusting or pitting.
Worse case from what you describe you could loose your return neutral and your ground leaving only a live hot wire waiting for someone to complete the circuit by touching the post. My 2 cents...replace it

[This message has been edited by ohioindy (edited 10-07-2011).]

The earth is classified as a corrosive environment, eventually dirt and water will get in to the casing and cause resistance in the wire and after a while you will build up heat, light wont burn as bright and finally it will just give up. I know UF is more expensive than NM but it just works better and less issues later down the road unless you get into with something which is why most people suggest putting anything like that in conduit.

As Syn said. Conduit is an inexpensive solution, and makes changing the wire later if needed much simpler.

(pure guess) I'm thinking it would cost an extra 10 bucks or so for the plastic stuff, (not counting glue) depending on how far you are going, heat and bend the pipe yourself for man points/ money savings.

Brad

quote Originally posted by twofatguys: As Syn said. Conduit is an inexpensive solution, and makes changing the wire later if needed much simpler. (pure guess) I'm thinking it would cost an extra 10 bucks or so for the plastic stuff, (not counting glue) depending on how far you are going, heat and bend the pipe yourself for man points/ money savings. Brad

I pay $1.09/ft for 2" sch40 PVC. I don't know what it cost in stores, I buy wholesale. I would DEFINITELY put it in some type of conduit or PVC.I am pretty sure ohioindy is an electrician, I would listen to his advice.

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I can ride my bike with no handlebars.

quote Originally posted by twofatguys: As Syn said. Conduit is an inexpensive solution, and makes changing the wire later if needed much simpler. (pure guess) I'm thinking it would cost an extra 10 bucks or so for the plastic stuff, (not counting glue) depending on how far you are going, heat and bend the pipe yourself for man points/ money savings. Brad

I sell 1" for 3.38 for a 10ft stick so if the post is 50 ft away that's 16.90 then 26.67 for 60ft of 12/2wg vs. 34.80 for 60 of UF wire.

quote Originally posted by Syn: I'm an electrician, Licensed by the state. stuff must be a lot higher in NJ because we well our sch40 for .89ft and that's just anyone who walks in off the street not a contractor price.

These were belled ends stuff. Not really even for electricity work. Ship tubes and the like. I bought them from a plumbing supply house, only due to convenience as I just sell that crap when someone doesn't want to make 2 stops and is buying stainless from me. I was just saying it is dirt cheap for PVC.

According to the National Electric Code, regular romex wire must be housed in conduit if run outdoors. However, UF rated wire can be run without conduit. So basically, your two options are to replace the romex wire with UF rated wire, or get 50 feet of conduit. Neither option should be very expensive, assuming you do the work yourself.

Use the wire that is intended to be buried. Don't bother with the conduit. In 20 years if you needed to replace the wires you wouldn't run them the same places anyways.

Make sure that run is on an GFI protected circuit.

I found regular Romex wire running out to my lamp post a few years ago.....it's been there for 30 years with no trouble. I suppose it depends on how much moisture is in the soil....mine is pretty dry.

I was sure there was romex that was safe to use alone. Ive ran into buried wires a lot of times. I have a lit sign in front about 30 yards out from the house that just has a buried wire. Its been there since at least 1985. Make sure you make some kind of map or diagram to keep track of where its at.

Yes I've been in the electrical union for almost 25 years. When I give electrical advice I have to give it 100% by the book. All wire run uderground must be underground rated. Putting Romex in conduit is not code. The wire must have a "W" rating which UF cable does.

I caved and ran a new UF cable. One thing I found interesting was the ground wire in the old UF cable had some patina on it. Not as much as the romex but some. The black and white in the UF cable were thhn wire with the extra clear plastic covering. So the ground wire in a UF cable is not 100% protected from moisture.

Thanks
Rodney

[This message has been edited by Rodney (edited 10-09-2011).]

quote Originally posted by ohioindy: The paper in Romex is the key. It will cause the copper wire to fail by taking in moisture and rusting or pitting. Worse case from what you describe you could loose your return neutral and your ground leaving only a live hot wire waiting for someone to complete the circuit by touching the post. My 2 cents...replace it

Heed what Mike /\ says. He knows that of which he speaks.

quote Originally posted by phonedawgz: Use the wire that is intended to be buried. Don't bother with the conduit. In 20 years if you needed to replace the wires you wouldn't run them the same places anyways. Make sure that run is on an GFI protected circuit.

For his application i agree, proper cable would be good enough. In other situations, conduit would let you do things like run a larger cable, or data faster line out to the shop or garage later much easier..