In article .com,
gtslabs wrote:
Yes, this is what I was thinking would work. My pressure switches are
double pole or L1, L2, M1, M2. I had trouble figuring how to wire
these with 3 phase wires. I have one leg going directly to the motor
and the other 2 going thru the switch. Perhaps this is not the correct
wiring but I could not easily find a 3 pole pressure switch at
graingers.

The three phase should go through a motor starter contactor,
with heaters to detect over-current when one of the three phases is
lost. So -- your pressure switch controls the coil of the contactor,
and the contactor switches the motor.

Enjoy,
DoN.
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