One light with two INDEPENDENT switches

[RSKY]

I cannot find a wiring diagram anywhere for this. I want to wire a light to come on by the entry door when a garage door opener activates. There are two openers in the garage. Is this possible without causing problems?

Thanks for your input.

RSKY

 

[bcp]

I think that just requires a 3-way switch on each opener.

Diagrams here:
Wire-3-way-switches

Bruce

 

[quicksandfarmer]

Do I understand that you want a light to go on when either, or both, of two garage doors openers is activated?

First question: do the garage doors have an output to an external light? Assuming they do, the answer depends on how that output is configured, and how the openers are wired. In the best case, if the outputs are electrically isolated, and the two openers are on the same leg of the electrical service, you can just run a wire from both outputs to the light, either one will light the light and having one on when the other is off or having both on at the same time. You can determine this using a voltmeter.

If the two openers are not on the same leg, when both are on the voltage of one will be the negative of the other, and the difference between them will be twice your line voltage (ie 220V). You can test this by turning both on and measuring the voltage between them with a voltmeter, if it is anything other than zero you have a problem. You might be able to solve this by having an electrician move one to a different leg.

If the opener outputs are not electrically isolated, when one is on and the other is off electricity will flow from the one that is on to the one that is off. You can test this by turning one on and the other off, and measuring the voltage. If it's anything other than zero you have a problem.

In summary: measure the voltage between the two outputs using a voltmeter in every possible configuration: both off, each one on with the other off, both on. If it is anything other than zero in any configuration, you have a problem. If it is always zero you can just connect the two outputs together and to the light.

If the simple connection isn't possible, there are other ways to do it but it requires using relays. We can cover that in another posting if necessary.

 

[RSKY]

I think I will give this up as a bad idea. I can see many problems. Thanks for your input.

 

[Mendonsy]

Another way to solve your problem might be one of the motion detector light fixtures??

 

[flyerdan]

If I understand correctly, what you'd like is an inside indicator light to alert you to an open garage door, correct? If so, I'd use the same type circuit that a dome light uses, and have the ground tied to the closed limit switches on the openers. That way you would be alerted to an open condition even if the door is open partially.

 

[RSKY]

Our garage has two doors and two openers. We usually close the garage door and walk into the house thru a door in the center back wall of the garage. The lights on the openers are on their front and so the back of the garage is always gloomy if not completely dark. I want to put a single fixture over this door that lights with the garage door lights and goes out with them. I would probably be better off getting two cheap fixtures side by side wired to each opener. RSKY

 

[kennyd]

I think it could be safely done with a low voltage circuit triggering a relay to operate the light. You could install a alarm contact/reed switch next to each door with a magnet on the door(s) to trigger the relay.

 

[SPIKER]

I would put in two small spot lights tied directly to the garage door openers LIGHT that exists now, point the spot lights where you want them.

Mark

 

[kennyd]

I think it could be safely done with a low voltage circuit triggering a relay to operate the light. You could install a alarm contact/reed switch next to each door with a magnet on the door(s) to trigger the relay.

Like this: