Renogy inverter remote switch wiring

[Boisblancboy]

Alright, got a wiring question on my remote switch for my Renogy 700 watt inverter. What I want to do is add a relay to the remote switch when grid power goes down to turn on the inverter. Well the remote switch wire has 5 wires: black, blue, red, yellow and green.

Any idea which one I should install the relay into?

 

[meetyg]

A picture would help.
But in general, you could check using a multimeter (in continuity mode), when the remote switch is not connected to the inverter.

What you are looking for are two wires, that don't have continuity between then when switch is off, but do have when switch is on.
So just start probing:
Flip the switch ON, put one probe of the multimeter on say the black wire, and the other probe on one of the other wires. If your multimeter shows continuity (beeps), now flip the switch OFF, and repeat those two wires. If it doesn't beep anymore, I would say that 99% it's those two wires. But to be 100% sure, you could continue testing all other two-wire combinations.