How to connect e.t.n motor breaker with contactor

A great question!

Connecting an E.T.N. motor breaker with a contactor requires some attention to detail to ensure safe and reliable operation. Here's a step-by-step guide to help you do it correctly:

Preparation

  1. Ensure the motor breaker and contactor are compatible: Check the specifications of both devices to ensure they are designed to work together.
  2. Disconnect power: Switch off the power to the circuit and verify that it is safe to work on.
  3. Identify the motor breaker terminals: The E.T.N. motor breaker typically has three main terminals:
    • L1 (Line 1): connected to the phase conductor
    • L2 (Line 2): connected to the phase conductor
    • N (Neutral): connected to the neutral conductor
  4. Identify the contactor terminals: The contactor typically has two main terminals:
    • CO (Common): connected to the coil of the contactor
    • NC (Normally Closed): connected to the normally closed contact of the contactor

Connection Procedure

  1. Connect the motor breaker to the contactor:
    • Connect the L1 terminal of the motor breaker to the CO terminal of the contactor.
    • Connect the L2 terminal of the motor breaker to the NC terminal of the contactor.
    • Connect the N terminal of the motor breaker to the neutral conductor.
  2. Connect the contactor to the motor:
    • Connect the CO terminal of the contactor to the motor's phase conductor (L1 or L2).
    • Connect the NC terminal of the contactor to the motor's neutral conductor.
  3. Connect the motor to the power supply:
    • Connect the motor's phase conductor (L1 or L2) to the power supply's phase conductor.
    • Connect the motor's neutral conductor to the power supply's neutral conductor.

Additional Considerations

  1. Use proper wire sizing and insulation: Ensure that the wires used for the connections are sized correctly and have sufficient insulation to prevent electrical shock or fires.
  2. Use a suitable contactor coil voltage: The contactor coil voltage should match the voltage rating of the motor breaker.
  3. Verify the contactor's operating current: Ensure that the contactor's operating current is compatible with the motor's current rating.
  4. Check the motor breaker's trip settings: Verify that the motor breaker's trip settings are set correctly to prevent unwanted tripping.

By following these steps and considering the additional factors, you should be able to connect an E.T.N. motor breaker with a contactor safely and effectively.