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Answered in 2 days by:
8/5/2017
Classic Car Mechanic: Classic Car Service, Classic Car Mechanic replied 11 months ago
Classic Car Service
Classic Car Service, Classic Car Mechanic
Category: Classic Car
Satisfied Customers: 5,230
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Hello. Welcome to Just Answer. Please allow me to assist you. The easiest way to accomplish what you want to to is when wither switch opens, the ground to the relay is removed. Wire as follows: Power Out to compressor: Pin 30 Power to relay coil (switched via AC switch): Pin 86. Power to relay from battery: Pin 87. Relay coil Ground: 85. Wire the switches in series to allow pin 85 to get a ground when the switches are closed. When low or high pressure is detected, the switches open, cutting the ground to the relay coil which allows the relay to drop out and kill power to the compressor.

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Classic Car Service, Classic Car Mechanic
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