What relay to switch low voltage devices?

Im looking to automate my garage door openers (3 of). At present I have radio controls for each door, where a single button will open the door, and that same button will also close the garage door. On the physical motor/control units themselves, there are two buttons, one for up and one for down.

There is mains power available next to each unit.

Im looking for a relay that:

  1. Can be mains powered (I can tap off the supply to each unit),
  2. I can set as a momentary switch, and when activated it momentarily closes a circuit which is independent of the mains power.

I can then either:

  1. Connect to the buttons on each of the units so a momentary activation of the relay would mimick somebody momentarily pressing a button. This would require 6 relays (3 doors, one "u"p and one “down” button on each)

If it is possible to have two independently addressable relays in one unit, then I can use one unit per door control reducing the number of units required to 3.

A neater solution may be to have one relay simply do a momentary press of a remote control button. In which case I can solder the relevant wires into a remote control unit, and connect to relays. If two relays are available on one unit, then I could then get away with just two units for the three garage doors.

Does such a Z-wave relay exist that would help with this?

Many Thanks :slight_smile:

This is what I bought the other day since I need to do a similar setup as yourself. Not sure if it will control more than one relay though.

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Thanks, though a bit more reading has thrown up some diagrams from both vesternet and fibaro showing the use of the fibaro relays to perform this exact task.



Using a single relay to press each button seems the way to go for me.

The helpful diagrams alone from vesternet are enough to convince me to buy the kit from them. Hopefully they may be kind with a discount once Ive gone round the house totting up what I want to buy. :smile:

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did you get it to work? I’m thinking doing the same thing as I was looking for a similar product to control the main water shutoff valve and a liftmaster swing gate.

Yes i did. The 212 relays worked brilliantly for this.

You should note that the relays need to switch the same voltage, hence if one is a 240v circuit and the other is 12v it will not work, but if they are both low voltage then that’s fine.

You can use a fibaro 212 relay to control different voltage items. It has to be the 212 relay, the newer 222 will only switch matching voltages.

I have relays for each of my garage doors. They are powered from 240v supply and they switch a 12v momentary circuit to activate the doors.

Wiring diagram on vesternet here:


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