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Looking for 120VAC latching relay that can be controlled by low voltage momentary switch Answered

I'm looking for a device that can switch 120VAC lighting and be controlled by a low voltage momentary switch.  This is just a standard residential lighting setup, so I have only 120VAC to the switch box.  I need this device to supply a low voltage signal to the momentary switch that in turn will control the latching relay for the lighting.  The momentary switches I have are low voltage dry contact closure switches rated to handle 32V AC/DC.  Does something like this exist?

Thank you for any thoughts you might have on this..



2 years ago

Do what I did for some of my mixed voltage setups ;)
If you check a car scrap yard for the relays and pay close attention on the markings you will often find lots that have labeling with writing similar to this:
12/24V 30A - This is often quite thick printed and the amps can be anything from 10 to 50 here, the 12V is for all cars, 24V you will find on some small trucks.
But next or under this marking you often find a rating for AC voltage too.
Usually 120V or in some cases even 240V.
The amp rating next to it will be much lower, for a 12V/30A relay it might be around 8A.
Any relay with a suitable voltage and ampere rating for your needs will do ;)

You can also check Ebay or your local electronics supplier for 12V relays, they are only a few bucks.
Either way make sure to get something with a socket mount and to have a spare relay at hand in case it fails one day, means for the ones from cars you should try to get the entire fuse box it was in ;)

Jack A Lopez
Jack A Lopez

2 years ago

Such things exist. I recall, one of these relays, made for switching power to electric lights, was made by General Electric (GE), and named "RR-7", and I found a data sheet for this, in pdf, here:


I have an uncle who used to live in a house, for which all the lights, in every room, were switched through a big cabinet of these relays. Also, the light switches in every room were actually low voltage switches, that switched a momentary low voltage signal to the relay controlling the light in that room. Also somewhere in the house there was a control panel, for to switch on or off any light in the house.

I think the voltage for these relay coils was 24 VAC.