# Electrical puzzle

• posted on June 8, 2009, 4:03 am
Hi,
This is probably too convoluted to try and explain here but I'll try.
I have two lights that I want to control with 3-way switches: 1 light is in the garage 60 feet away and one light is the house. I plan to put them on the same circuit.
In the house I have two 3-way switches: H1 and H2 In the garage I have two 3-way switches: G1 and G2
I planned to share the neutral, so I put in the conduit one 14/3 and one 14/2. But now it seems to be that I'm one wire short!!! The problem is that while the garage light is wired H1-G1-light, the house light needs to be wired H2-light-G2 and I just can't come up with a diagram that will make it work.
Can anyone help out of my predicament?
Thanks!
Aaron

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<%-name%>
• posted on June 8, 2009, 5:13 am
Aaron Fude wrote:

the diagrams at http://www.electrical-online.com/wiringdiagrams.htm may be of help
if I understand what you are trying to do, you may need to wire the H1G1 set as "Basic", and the H2G2 set as "Variation #3", involving a total of 6 wires between house and garage. Note that Var 3 really does not have a "neutral" between the house and garage !!

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<%-name%>
• posted on June 8, 2009, 2:48 pm

powerH->H1->H2->lightH (basic 3-way switch) powerG->G1->G2->lightG (also basic 3-way switch)
Between H1 and H2 you would find 3 to 4 wires (ground, neutral, and two traveller wires). Ground wire doesn't have to come from H1 to H2; it could come from anywhere, I believe.
Between G1 and G2 you would find the same.
In theory, you can make it work with 4 wires between the house and the garage (two travelers from house to garage, and two travelers from garage to house). If you do this you'd end up with:
powerH->H1->G2->lightG powerG->G1->H2->lightH
The only wirings you change is between H1->H2, and G1->G2.
Doing this would mean combining hot from one source with neutral from another source. This is very unusual way to wire stuff. If one of the sources has a GFCI or AFCI this kind of wiring would cause problem. It may also be against electrical code. And even if it isn't, I wouldn't do it if I were you.
To avoid mixing hot and neutral, you need 3 wires between H1 G2, and G1 H2. So, the best solution is to replace the 14/2 in the conduit with a 14/3 so you can have 6 wires.
If you don't want to change the conduit, you can choose to have one of the lights (the garage or the house) works as a 3-way, and then wire the other light as a normal one-switch light.

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<%-name%>
• posted on June 8, 2009, 11:08 am

Assuming you have 2 two gang boxes at each location and two 3way switches at each location. You have to have 2 wires at either location going to each light. you need a feed brought into one of the switch locations, and you'll need 3 wires going from each switch to it's corresponding switch location

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<%-name%>
• posted on June 8, 2009, 12:25 pm

Think of it this way: 2 lights in hallway with 3/w at each entrance. Same connections you are searching for.

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<%-name%>
• posted on June 8, 2009, 12:38 pm

Of course you're one wire short. A 3-way switch needs 3 wires. Two 3-way switches requires 6 wires. "Sharing the neutral" doesn't have anything at all to do with this. That's a completely different matter -- suggest you Google on "shared neutral circuit" or "Edison circuit" for an explanation.

Replace the 14/2 cable with a 14/3.

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<%-name%>
• posted on June 8, 2009, 3:29 pm
Aaron Fude wrote:

Nice explanation.
If wiring it with cables you need a 3-wire for each light. If you need power at the garage you need another 2 wire.
If wiring with conduit and wires you need 6 wires (not including ground). If you need power you can still use 6 wires and connect one of the 3-ways as a "California 3-way".
If you used a 3-way at each end to control both lights at the same time (2 switches total) you could also use a "California 3-way" (also gives power at the garage). Requires 4 wires in conduit. Since a couple codes ago this requires a 4 wire cable.
You can use what you have if one of the 3-ways uses an X10 control.
(You don't detail your wiring method. Cables in buried conduit have to be UF (not Romex).)
-- bud--

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<%-name%>
• posted on June 8, 2009, 5:46 pm

Aaron How do those two cables reach the garage? Is the garage attached or detached? What kind of cable did you use? What Country, State / Province are you located in? Answer those questions and we can give you much better answers. -- Tom Horne