This wiring diagram shows a Direct-On-Line (DOL) circuit for a 3-phase induction motor. The 3-phase power supply provides the electricity to the motor. A contactor makes the connection between the motor and the power supply. Start button ignite the contactor coil, which closes its contacts. Then the circuit completes and motor start its rotation. The thermal overload relay is for safety purpose to keep it safe from surpass current. This wiring helps you to understand flow of control from start/stop buttons to the contactor activation and overall motor operation and protection.
