Is there such a thing as 120v A/B switch?
I’m considering running a circuit for a 120v, 1200w quartz heater that draws 10 amps. The heater has a standard 3-prong 15 amp plug (hot, neutral and ground). The instructions say that in the U.S. and Canada the heater is only to be used on a 15 amp circuit.
I want to have two of these heaters on one 15 amp circuit. One would be in my garage, and I would never even want to run both at the same time. So I’d like some sort of A/B switch that I could use to switch available power from one to the other so it would never be possible to run both at the same time. I wouldn’t be using this switch to power on either heater. I plan to have a properly rated timer switch near each heater to turn them on and off.
I don’t know if an A/B switch like this is available, and how large it would be. Ideally, I’d like to have one that would fit in a single or double gang box.
Does anyone have any suggestions?
Thanks
Replies
For 15 amps, you could probably use a normal 3-way to switch the power leg like this:
/O-------|--------> to heater #1
Power -----|O-----/
O -------|--------> to heater #2
^ 3-way switch^
|--------> to heater #1 |
Neutral ---------------------|
|--------> to heater #2
Is this Code approved? NO idea!
Mike Hennessy
Pittsburgh, PA
Do you mean like a the same type of switch you'd use for a 3-way switch configuration in a hallway?
Mike beat me to the answer, but yes he's talking about a conventional 3-way light switch.
Just make sure you wire the power feed to the common or odd colored terminal.
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Riversong HouseWright
Design * * Build * * Renovate * * ConsultSolar & Super-Insulated Healthy Homes
What Riversong said, complete with the be-you-ti-ful, full color picture, with circles and arrows and a description (albeit not on the back). ;-)
Still don't know if it's code to use a 3-way without it's partner, though. I can see where it might cause somebody to get to scratchin' their head somewhere down the line.
Mike HennessyPittsburgh, PA
Yeah, it's definitely something I'd undo if I sold the house. The heaters would come with me, and I'd just leave the outlets behind.
I'm not quite sure why you need to do anything with three way switches or anything like that. Since you'll be running only one heater at a time the circuit won't be overloaded.
I want to make sure that both heaters cannot be turned on at the same time.
How about a sign that says: "dont turn on both heaters at the same time"? :>)
I think you could also do it more clearly with a conventional SPDT toggle switch. All the hardware you need cen be found in the electrical dept. or Radio Shack.
I made something similar for my attic - in that case I allowed the lights to be run off one of two different circuits. I'd still have the light I needed if I was reconfiguing the other circuit.
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
If your hair looks funny, it's because God likes to scratch his nuts. You nut, you.
Yeah, a 3-way switch. Unfortunately you can't get a true toggle anymore in a wall switch (except maybe mail-order), so try not to operate the switch under load too often.
Hi Dan--
I'm not sure I follow what you're saying about not operating under load too often. If I install a 3 way switch, it will always be in one position or the other (and the electricity flowing through it) whenever one of the heaters is on.
Try not to flip the switch while one of the heaters is on.
What is wanted is not the will to believe, but the will to find out, which is the exact opposite. --Bertrand Russell
Okay. With them being on timers, that would be pretty easy.
But why does it matter if they're on when the switch is flipped?
"But why does it matter if they're on when the switch is flipped?"Whenever a switch is "flipped" there will be some arcing as the contacts close or open. With a 10A load like your heaters, the arcs will be bigger than with lighting circuits for which residential switches were designed.The switch recommended by rasconc [102676.13] is an industrial device that is designed for operation under 12A loads.
BruceT
I've been using a 3 way switch in this config for 5 years now, no problems, but I use mine to choose 1 of 2 power sources coming in, 1 is hot all the time, the other is from a photocell, hot only at night, the power out from this switch then feeds individual light switches. When I'm away I use the hot at night leg to control security lighting, when I'm around I switch it to always hot and turn on/off the lights from their own switches .. no idea if it's legal .. inspector looked at it, I just didn't say anything .. would be interested in knowing if it is legal ??? The wires are all clearly labeled ...
You are describing a single pole, double throw, center off switch. Actually you were describing one without an off position. Here is one that will do what you need. The second link will show you more options.
http://www.leviton.com/OA_HTML/ibeCCtpItmDspRte.jsp?sitex=10021:22372:US&item=8632
http://www.leviton.com/OA_HTML/xxlcfbuibeCSrdSrchResults.jsp?cg=&kw=single+pole+double+throw&ds=0&dr=20&st=kw&cpg=0