Rian-II

Thanks @Louisvdw, that's a great idea. I also thought it could be pins 3 and 4 for the switch, considering pins a and b looks like it's at the coil.

This is the relay. Any advice on which pins to connect to? Will really appreciate the advice!

Nevermind, it turns out it's the difference between a relay that switches on 12V DC vs 220V AC. I already had the Sonoff Basic R3 (which requires AC input) and would like to put the Sonoff and Relay setup inside my DB Box (and make sure it is within regulations), hence I went with the 220V AC relay. It is much more expensive though.

Hi, does anyone know where I can get 30A relays for 240VAC at the R30-R40 that everyone speaks of? Everywhere I look they only start at ±R210. This is for the Sonoff and relay config discussed on this thread.