Home Improvement Stack Exchange is a question and answer site for contractors and serious DIYers. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I just bought a wall timer to replace a three-way switch. The wall timer comes with three wires, one for the common screw wire, and the other two are for the travelers, with no place for a ground wire. When I took out the three-way switch it had the common and the two travelers that I needed and it also has the ground wire.

My question is, where do I put or what should I do with the ground in this situation?

I called the manufacturer and the guy said that "a ground is not needed in this situation and that I should just tape it off". Is that what I should be doing?

Here's a picture of the back of the timer. enter image description here

share|improve this question
Where are you installing the switch? – Edwin Jan 9 '14 at 3:42
What country, is what I mean. – Edwin Jan 9 '14 at 4:07
I'm in the United States. – dalutulak Jan 9 '14 at 4:34

If the switch has no exposed metallic parts after installation—and has no ground terminal—then a ground connection to the switch is not needed. Connect the three ground wires together (one from the power source, and two for the travelers).

If the timer has exposed metal, then there should be a ground screw. If the junction box it is installed into is metal, ground the box by adding a fourth ground wire into the junction with the other three grounds, and screw the other end of the wire to the j-box. Use metal screws to install the timer into the j-box: This grounds the timer and was the standard way of house grounding up until sometime in the 1960s.

If the j-box is not metal, but the timer has some exposed metal, run a ground wire to it and fasten it securely somehow. (Maybe add link to a photo of the timer for better advice.)

share|improve this answer
If the J box is metal, regardless of the switch, it needs to be grounded (in the USA). – Bryce Jan 9 '14 at 10:48
I added a picture in my post. – dalutulak Jan 9 '14 at 18:34
@dalutulak: is the j-box metal? – wallyk Jan 9 '14 at 18:36
@wallyk nope it's plastic – dalutulak Jan 9 '14 at 23:01

If there is no ground terminal/wire then there must be no exposed metal parts on the switch and thus no potential for a shock or short.

share|improve this answer
You've got it round backwards. The OP has a grounding conductor, but the new switch does not have a grounding terminal. Also, simply connecting a wire to a nearby water pipe is NOT a proper grounding method. – Tester101 Jan 9 '14 at 10:35

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.