110v Relay Needed

[fidowanttobe]

Reaching out to the electricians here. I am looking for a relay to control 3) 4' fluorescent lights off of my garage door opener and I don't know which relay I need. Millions to choose from. Can someone out there tell my specifically what relay I need? I will open up the opener and mount a box to it with the relay contained, then run the wires to the lights. I'm confident in my wiring abilities, just need the relay.
Without sounding rude, please don't come up with alternative ideas, (many people have ) as I have thought this thru.
I want to use two relays, with both of the "output" hot leads going to the fluorescent fixtures.
Wall switch to relay1 coil, Garage door light power to relay2 coil, hot from ceiling receptacle box to "in" side of switched relay contacts on both relays, out to fixtures from "out" side of switched relay contacts on both relays. If either relay is on, the lights are on. If this is do-able, let me know.
Thanks

 

[Mendonsy]

The question is ...... what voltage (and current) does the door opener have available to operate the relay??
You could probably use something similar to these with the matching relay socket but you need to know the coil voltage.
General_Purpose 15A 3PDT relay

 

[Fallon]

Tie into the light bulbs on the opener... would mean 120v.

 

[TemporaryKubotaOwnerMark]

There's no ONE right relay. Like Fallon said, tie into the light bulb on the opener, so you need a 120v relay that's triggered by 120v. Now to determine how big it needs to be, add up the loads. How much current do they all draw? Add about 20% (minimum) to that as a safety margin, and there you go. Won't hurt to go double, either.

 

[franklin2]

Are you going to buy online or locally? Locally, a HVAC supply store would have a good selection of contactors for furnaces and A/C systems that you could use. Just make sure the coil is 120v. Common coil voltages are 24vac, 120vac, 220vac. You will need a larger contact rating than you would think, since you are turning on a fixture with a ballast. I would go ahead and try to find one with 20 amp contact ratings. Then you can follow through with your wiring, if you have a 20 amp circuit, it should have a 20 amp circuit breaker, 12 gauge wire throughout, and the 20 amp contacts on the relay will fit right in.

If you are ordering online, something like this would work. It's a 30 amp unit, bigger is ok.

Amazon.com: Packard C23B 2 Pole 3 Amp Contactor 12 Volt Coil Contactor: Home Improvement

 

[fidowanttobe]

Thanks for the response guys.

 

[CharlieS]

Not to rain on anyone's parade, but there is a potential for disaster here. If the entryway light switch is not on the same phase in the panel as the door opener circuit there will be a potential to feed the lights with 240 volts if both switch's are energized.

And what about the time delay in the door opener light? when that circuit opens to turn the light off after the set period of time, room lights will go off also since one relay will be controlled by that means.

What you really need is a single contactor with a safety interlock so that it can't be energized by two sources.

 

[Industrial Toys]

It's true. I would have preferred to do this using low voltage and then maybe solid state relays. I do this kind of thing all the time, and there are always some kind of issues.

My latest jackshaft openers all come with remote lights (that I don't even use). I am not even sure what signalling system they use.

 

[franklin2]

Not to rain on anyone's parade, but there is a potential for disaster here. If the entryway light switch is not on the same phase in the panel as the door opener circuit there will be a potential to feed the lights with 240 volts if both switch's are energized.

And what about the time delay in the door opener light? when that circuit opens to turn the light off after the set period of time, room lights will go off also since one relay will be controlled by that means.

What you really need is a single contactor with a safety interlock so that it can't be energized by two sources.

Good catch on that. I didn't really read what he was doing till you said something. I was just concentrating on the relays and sourcing them. I don't think the lights would ever see 220v, if both relays kicked in with different phases feeding them he would have a dead short phase to phase and trip some of the breakers correct? Assuming he would tie the output of both relays together and feed the lights with one wire from that.

 

[LittleBill21]

why wouldn't he be tying into the main circuit he was using for the light switch, he's just replicating the light switch and wiring in parallel, should only be using the opener as a signal for the contactor.