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Pool guy · Jul 24, 2005, 09:19 AM

Help,

I have a Pool timer that is wired 220V for the pool pump. I have a separate 110v wire that was switched from my guest house to turn the pool lights on. There is a short in that wire now, possibly a wire breakage in the cement from shifting? Anyway, I've since unhooked it. My question is, I'm trying to see if there's a way that I can wire a 110v switch off from the pool timer to turn the pool lights on and off, instead of running a whole new 110v? Any help would be appreciated.

labman · Jul 24, 2005, 09:42 AM

220 volts uses 2 hot wires, and 110 uses a hot wire and a grounded neutral. Many 220 devices also have a 110 component, and are wired up with a 3 conductor plus ground cable. If the pump timer has the third conductor, and enough capacity to support it and the lights, it should work. Keep the load on a #12 below 20 amps. If only 2 conductors to the timer, and it is the hot wire to the light that is shorted, and the neutral is still good, perhaps you could continue using the white wire, and power from one of the hot wires to the timer. I am not up enough on code to say that it is OK. Is the timer, or the pump 220? Often on things such as a stove or dryer, the heating elements are 220, but the timer is 110.

Pool guy · Jul 24, 2005, 10:06 AM

Thanks Labman,

I was a little confused so I went out and looked at the timer. Now I think I'm more confused... lol there's 4 posts on the timer with the metal straps being on the 1rst and 4th post. There's a wiring coming into the box which consists of a black, white, and one bare copper wire. Its wired to the 1rst and 4th post. The wires going to the pump are black, white, and also the bare copper wire. They are wired to posts 2 and 3. I have two voltage checkers and I think one of them must be bad... cause when I touched post's 1 and 4 I got 240v with one, and the other was only 110v... grrr I'd hate to go buy another one just to see which one is bad. Anyway, I'm just looking for a way to get 110v out to an outside switchbox for a single light.

labman · Jul 24, 2005, 10:41 AM

Sounds like the timer is indeed a 220 or the 240 volts you measured as is more common. An easy check of your meters would be the black to bare copper. Should be about 120 volts. Trust whatever meter give you that. If 240, the white will show 240 to the black and 120 to ground. If 120, the white should no more than a few volts to the bare copper.

Pool guy · Jul 24, 2005, 11:42 AM

You are correct sir, thanks. Measured 120v when testing the black wire on post #1 and grounding at the bare copper wire. Its probably not the correct way to do this, but I'll run a jumper off the black wire and the bare copper wire into the outside on/off switch box for the light. Any ideas on what to do with the white wire? Should I run it to a small breaker box first? I hardley ever run the pump and the pool light at the same time. Thanks again :)

labman · Jul 24, 2005, 12:05 PM

Using the bare wire definitely violates code and cuts your safety margin. At least verify the white wire to the timer is a hot wire first. If it is, look into reusing the existing white wire for the lights. The fewer electrical short cuts around a pool, the better. If things have a proper GFIC, I don't think it will work using the bare wire.