TV-lift in Homey

I have a TV-lift (TS700A). To control this I use a Sonoff RF-Bridge, but this setup is not reliabel.

I have found out that the up and down functions can be controlled by a wired button connected to the TV-lift´s circuit board. See the pictures.

The button has 3 wires running on 5 volt. Then the left wire touches the center wire the TV-lift will go up. Then the right wire touches the center-wire the TV-lift will go down.

I’m therefore looking for a double 5V relay to control the up and down function from Homey. I know this is explained here: Tv lift met homey aansturen - #4 by Mikzorzz. But this seems to use a 230V relay, that will fry my board. But i cant find any 5V relays.

I´m thinking to use a Shelly Plus 2PM that runs on 24V and then use 2 step down buck converter to go from 24 volt til 5 volt. But this also requires a 24V power supply, to provide power to the relay. To be honest, this setup seems a little clumsy. But is this setup even possible, and have I missed something important?

Maybe someone has a better idea to control the tv-lift in Homey without using RF433. I will prefer a relay using WIFI or Z-wave, but this is not a requirement. Thank you.

You can go with this:

You connect the middle wire to the IN port The left wire to Q1, the right wire to Q2.

But there are a lot of other solutions what can work…

Thank you. But this relay provide 24-30 V. The voltage between the wires from the circuit board is only 5V. Is this not a problem?

When you connect these 5Volt wires to the relay-dry-contacts, that is never a problem, whatever the voltage is (as long as it is not higher than the max. contact voltage).

Like Jan says.
Example, I’ve a Shelly 1 and it has a dry contact (Dutch: potentiaal vrij), which is completely separated from the input voltage.
You can power the relay with f.i. 230V mains power, and switch the 5V wire using the dry contact.

Now i understand. I will try with a dry contact relay. Thank you very much.

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