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cmb4609
Oct 2, 2011, 09:44 PM
I have another question, I have wired a three way switch a few times the basic way switch, light, switch, with 14/3. I was wondering if there is any way possible to use 14/2. I have one switch in the house, there is a line that is 14/2 already in pvc going out to the garage there is another switch out there next to the door and a flood light at the peek of the garage. I can have power start a ether end in the house or the garage with no problem. Is there any way to use the 14/2 so I don?t have to pull 14/3 through the pvc.

WallyHelps
Oct 3, 2011, 06:01 AM
I have a way, but I don't know if it would pass electrical code or not. Use your judgment as to the safety of this idea.

The concept is to use a conventional 3-way switch in the garage along with a SPDT 110v relay (http://static.electro-tech-online.com/imgcache/502-110901_15lo.jpg) that is controlled by the house switch. In essence, we are converting the indoor 2-way switch into an outdoor 3-way switch. You would need to make sure that the relay coil is rated for continuous duty, as it would be energized the entire time the indoor switch is "on".

I've attached a rough schematic to show how this works.

Best of luck, I hope this is helpful.
WallyH

hkstroud
Oct 3, 2011, 06:55 AM
No. Only way is a wireless 3-way switch.

cmb4609
Oct 3, 2011, 08:51 PM
WallyHelps- have you tried it? Why wouldn't it pass electrical code? Would the relay over heat?

WallyHelps
Oct 4, 2011, 05:45 AM
WallyHelps- have you tried it? Why wouldn’t it pass electrical code? Would the relay over heat?
I haven't tried it, but a relay coil rated for continuous duty shouldn't overheat (i.e. it can be continuously energized). I think with the proper enclosure and wiring practices, this would be safe--however, the electrical code may not allow this sort of setup.

You may consider Harold's suggestion regarding a wireless switch. I just don't know what the range of these things would be.

Best of luck, be safe.
WallyH

tkrussell
Oct 4, 2011, 07:00 AM
I don't see how the wiring diagram would work.

The relay coil is in series with the lamp?

The lamp neutral connects to a switch?

Where is the input feed?

The simplest method would be to install a 3 wire cable in place of the two wire.

Or use the wireless devices.

cmb4609
Oct 4, 2011, 02:49 PM
tkrussell- that's probable what I will end up doing, pulling new line. It was worth a shot asking.

WallyHelps
Oct 5, 2011, 07:52 AM
I don't see how the wiring diagram would work.

The relay coil is in series with the lamp?

The lamp neutral connects to a switch?

Where is the input feed?

The simplest method would be to install a 3 wire cable in place of the two wire.

Or use the wireless devices.
Your confusion is probably due to my artistic "ability". The relay coil is simply hooked to hot and neutral in series with the indoor switch. Thus, this switch either energizes the coil or not.

The lamp is hooked in a conventional 3-way switch arrangement, with one standard 3-way switch (in the garage) and the SPDT contacts of the relay as the other "3-way switch".

The input feeds are shown on the diagram as the circles denoted "HOT" and "NEU". Thus, the input feed comes from the garage side.

I am 100% sure this will electrically function, the only question is whether code is violated or not.

Hope this clarifies my answer.
WallyH

P.S. I will also agree that pulling a new wire and using a 3-way switch in the house is probably the way to go. More work? Yes. Cheaper? Possibly (nice relays aren't cheap).

UPDATE: I added a re-drawn diagram that separates the power and control circuits. Hope this helps.

ohb0b
Oct 6, 2011, 11:01 AM
Electrically, it would work BUT... you are essentially building a small control panel, and unless you can get into the UL White Book, good luck getting an inspector to buy off on it.

If you do decide to install this, the relay coil must not only be rated continuous duty, the contacts have to be rated for the load.
Also, the diagram shows the relay switched on the neutral side, which is another code violation.
Best bet, go with the wireless switches.