Automatic Water Pump Control Using Electric Contact Pressure Gauge | Wiring Explained

Added: 2026-05-22

[00:00:00]Do you know how to wire an electric contact? Pressure gauge for an automatic water supply system. Let's go through it step by step. First, take a control power line and connect it to contactor coil terminal A1 and terminal 14 of the intermediate relay. Next, connect the live wire to terminal 96 of the thermal overload relay. Then connect terminal 95 to the contactor terminal to create the self-holding power circuit. Now connect the electric contact pressure gauge.

[00:00:29]Connect the yellow common wire to terminal 14. Connect the green lower limit terminal to contactor coil terminal A2. Then connect the red upper limit terminal to terminal 13 of the intermediate relay. After that, connect the contactor terminal 13 to the common terminal 12 of the intermediate relay.

[00:00:50]Finally, connect terminal four of the intermediate relay to contactor coil terminal A2. The wiring is now complete.

[00:00:57]When power is turned on, the contactor energizes and the water pump starts supplying water automatically. As the pressure reaches the upper limit, the intermediate relay activates and disconnects the self-holding circuit, causing the pump to stop. When the pressure drops back to the lower limit, the contactor energizes again and the pump automatically restarts, restoring the water supply. That's how an electric contact pressure gauge controls an automatic water supply system.