Switch sensor and relay device?

Hardware
1

I’m looking for a device that will sense a switch contacts and provide a relay output.

I’m relatively agnostic about communications protocol. Have an extensive Homematic installation but also have zigbee capability, Wifi is an potion too.

I want to patch this in to several dumb appliances, Dishwasher, Washing machine and tumble drier to allow them to be ‘initiated’ by a button press and then actually started via the relay operating the original ‘start’ button on the appliance at some later time when HA decides power is cheap or in plentiful supply. I could also use it to operate driveway gates etc.

Anything like that on the market? I can also make up something with ESP32 devices, perhaps even add a small display to show what state the device is in. A single button could be used to cycle through options - Start when best, start immediately etc.

2

In theory it’s ok, bun in practice to modify start button wiring of appliances is PITA.
If you have appliances that continue automatically after blackout, you could use Shelly pm to cut off power right after start and then continue when wanted.

3

Diswasher will restart but the rest wont. I’m happy with the PITA approach.

I can see me having to knock something up.

4

At least that, probably the most difficult to modify.

Have a look at Shelly Uni plus, could be the easiest way to go (depends what control board voltage you find inside your appliances)