AC Power Contactor Control with 24V DC Relay In this setup, the 24V DC power supply energizes the relay coil, which in turn controls the contactor. When the relay coil is energized, the relay contacts close, completing the control circuit of the contactor and allowing the AC power to flow to the load. When the relay coil is de-energized, the relay contacts open, interrupting the control circuit and de-energizing the contactor, thereby turning off the load. CNC Electric can just be your trustwort