How do I wire a 3-way switch to control one light?
I replaced some old switches in my kitchen with some updated Decora 3-way switches. Each switch used to control the overhead light, but ever since replacing the switches they no longer work properly. You can turn the light on with one switch, but if the other switch is in the “off” position, the other switch becomes inoperable.
I’ve tried several wiring combination’s, starting with using the Red wire as the “traveler” on both switches, as well as using the black wire from the same wire “set” as the red wire as the traveler. No matter what combination I try though, I cannot get it to work right. Am I missing something?
In stead of typing, I wish I could just draw you a diagram – its really easy.
I am an electrical contractor, this is how I would fix it.
#1 turn off the power.
#2 Disconnect all of the wires – remove the switches.
#3 turn the power back on and determine which wire is supplying the power. Use a voltage tester, mark the hot wire with black electrical tape.
#3 Wire-nut all 3 off those wires together (the hot and the other 2 wires – runners/travelers. But make sure that at the other box that the wires are not touching anything as 2 of those 3 wires will now be live.
#4 at he second box – use a voltage tester to determine which 2 wires are hot – these are your runners/travelers.
#5 mark the wire that is not hot with black electrical tape, this is your ‘load’ wire, it feeds power to the lights.
#6 turn the power off.
** On a 3 way switch there are 4 terminals
2 of them look the same – these are for the runner/travelers wires.
1 terminal is darker – it is for the power, or load wire.
1 terminal is green – its for the ground wire.
#7 attach the wire with the black electrical tape to the terminal that is a darker color. Attach the 2 runner wires to the terminals that look the same. Attach the ground wire (if you have 1) to the ground (green) terminal.
#8 turn the power on and test – your done.
Good Luck.
Electrical dictionary: Smart switch (decora)
