The switch has + and - on the center wires.
Operating the switch in one direction sends + 12 VDC to the relay control
Pushing the other way reverses the polarity to the relay control.
The relay will not operate if the house batteries are dead OR if the 50 Amp DC breaker near the batteries is tripped.
See this thread:
https://www.thorforums.com/forums/f8...kin-27421.html
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