I am trying to fnd a 240v relay that can handle 20 to 40 amps. Would like a latching relay or even better, one with local control so that if the automation system dies, the loads can still be controlled. Anyone have suggestions on a product. I searched but am not sure what to buy …
With loads like that you’re best rolling your own.
Disclaimer:with loads like that you’ll likely cause a fire if done wrong.
I would use a sonoff to drive a contactor which is designed for the load. You then have the option to include a switch in parallel with the sonoff to manually turn the contactor on.
If you need a diagram I can a bit later.
Something like this is good https://www.screwfix.com/p/british-general-40a-dp-contactor/1836p
This should work for you:
That’s a nice option Chris. I did not realise there are higher power ones.
I wonder if one can flash it with custom firmware.
Found another option on AliExpress
Easy to control with an ESP8266.
However, I would really like to find a latching relay.
Have you considered Thristor load switching rather than relays?