Electrical question - 3-way switch wiring dilemma

[J D Thomas]

I have a circuit where I've installed a pair of 8' fluorescent T8 fixtures. The fixtures are at the beginning of the circuit and I want to wire in a pair of 3-way switches at the end of the run. What's making it complicated for me is that the wiring in the circuit has 3 wires plus a ground. And both the black and red wires are hot. I'm assuming I don't need both hot wires, but I'm not sure how to configure it all including the neutrals. The lights work now when the circuit is on, and the 3-way switches have a 3-wire run between them. From this point I'm at a loss as to how to get the switches to control the lights.

Any help and advice would be appreciated.

[Jason Roehl]

Here's a diagram that should help:

http://www.electrical-online.com/3waydiagram.htm

Notice that the neutrals are all tied together. Then you take the hot/black coming into the light and that goes to the odd-colored screw on the first switch (usu. black), then you wire in the red and black as shown to the second switch (notice the orientation of the screws, that's the important part), then you run the switched hot out of the odd-colored screw on the second switch to the light.

[Rob Russell]

J D,

You should request that your name be changed to your full first name. Click on the "Contact Us" link at the bottom of the page. That is an SMC requirement and I'm speaking as a Moderator on this. PM me if you have questions or a problem with that.

Jason,

Your diagram is good - but I don't think it fits what JD needs. The wiring when the fixture is at the front of the circuit is different than when it's at the back end.

JD,

The common term for that wire is the "traveler" or "switched" leg. The way a 3, or 4+ switch wiring setup works is to have (2) conductors that carry the hot current. The electricity switches shift back and forth between the 2 conductors as you move through the switches.

I don't remember the sequence for wiring a 3+ way circuit where the fixture is at the front end. I'd have to go look that up.

[glenn bradley]

Closer: http://www.rightautos.com/imagelookup?html=http%3A%2F%2Fwww.electrical%2Donl ine.com%2F3wayvariation6.htm&thumb=http%3A%2F%2Fsp1.yt%2Dthm%2Da01.yimg.com%2Fi mage%2F25%2Fm4%2F2876488639&file=3%2Dway%2C+multiple+lights+in+middle%2C+conne cted+with+4+wires+between+lights.gif&thumbheight=134&width=480&height=462&size=12
This has a lot of variations: http://www.rightautos.com/imagelookup?html=http%3A%2F%2Fwww.thecircuitdetect ive.com%2F3wayschemes.htm&thumb=http%3A%2F%2Fsp1.yt%2Dthm%2Da02.yimg.com%2Fi mage%2F25%2Fm4%2F2962405984&file=4wy.gif&thumbheight=55&width=682&height=252&size=17.5

[Gene Michael]

You may want to pick up the Black and Decker 'Complete Guide to Home Wiring.' The illustrations are easy to read and make 3 ways a snap.

[Jason Roehl]

Jason,

Your diagram is good - but I don't think it fits what JD needs. The wiring when the fixture is at the front of the circuit is different than when it's at the back end.

Rob, I considered that before I posted the link, but decided there's no difference. The light needs a hot and a neutral. The hot gets switched. So the hot has to leave the light fixture (right after it comes in), go through the 3-way switch assembly, then come back into the light fixture to be attached to the light. The neutrals just all get tied together. Don't be constrained by how the diagram is drawn--think of the whole blue area in the diagram as the light fixture, except for the part containing the two switches. Trust me, it'll work.

[Brian J Holmes]

Here's the easiest to read diagram I found:
http://images.lowes.com/general/3/3way_blownupbeginning.gif?

Here's some other wiring diagrams:
http://www.homeimprovementweb.com/information/how-to/three-way-switch.htm

http://www.electrical-online.com/Fall202.gif

[J D Thomas]

I'm sorry I haven't responded until now. I've been away since I posted last weekend and today I intend to get to the bottom of this issue.

Thanks to all the great responses and advice. I'll keep you posted on the progress here.

J D Thomas
ThomaStudios

[J D Thomas]

Well I finally got back up to the crawlspace today and reexamined what I'd done last weekend. Turns out all that squatting and scrunching of my body must have had an adverse affect on my grey matter. I changed two connections at the first fixture and double-checked my way back to the switches, and now all is well. Thanks to everyone who chimed in with some advice.

[Chris Padilla]

Just last weekend I was swapping out some 3-way switches (wifey wanted ivory colored switches instead of the white ones *groan*) and upon rewiring, the light didn't work correctly. The one I changed would only turn the light on. Well, silly me, I swapped the black (hot) and red (traveller).