ESP32 Forum

I've got a little machine that lets me switch the area where my robotmower goes. This is a manual switch, but I would like to automate it with an ESP32. I think I should use a relay with the ESP. But which relay should I use for this? Can somebody give me advice?
As you can see on the photo, the switch just changes the connection between two circuits. I would replace the manual switch with the relay.
Thanks a lot.

You want to look for a "single pole dual throw" (SPDT) relay, i.e. one with one input ("COM") and two outputs ("NC" and "NO"); apparently one which can switch up to 10A at 36V DC to match the original part's specs. I guess there are nowhere near 10A in the circuit, so a lower-spec relay will likely work just fine.
Since the ESP outputs 3.3V the relay needs to be able to be controlled by that voltage (a 5V relay may not work).
I suggest to get a relay module instead of a bare relay, as these usually include the required flyback diode and may already accept 3.3V input and lower the output current drive requirement on the ESP's IO pin.
Something like this for instance.
If you want the relay, like the switch, to remain in its last state even when power is cut, you would look for "latching" SPDT relays.