Wire break in phase A
Beckhoff · TwinCAT 2 NC
¿Qué significa 4632 ?
A wire break (loss of continuity) has been detected or reported in phase A of the motor connection, either within the drive or at the terminal. This critical fault means one of the motor phases is open-circuited. Attempting to operate the motor with a phase break can lead to severe damage to both the motor and the drive due to unbalanced currents.
Causas comunes
- Open circuit in the motor power cable for phase A between the drive output terminal (e.g., U) and the motor terminal.
- Loose or corroded connection at the drive output terminal U or the corresponding motor terminal (e.g., T1).
- Internal winding break in phase A of the motor, preventing current flow.
- Faulty motor contactor or relay with an open contact for phase A in the motor power path.
- Drive's internal current sensor for phase A (e.g., R0-04) malfunctioning or reporting zero current despite motor operation.
Pasos de reparación & Lista de verificación
Haga clic en los pasos para seguir su progreso.
- 1
Power down the drive and motor, then measure the resistance of the motor cable phase A (e.g., from drive terminal U to motor terminal A/T1) using an ohmmeter to confirm continuity.
- 2
Disconnect the motor cable from both the drive output (U) and the motor input (A/T1), then visually inspect and retighten all connections.
- 3
Measure the resistance of the motor windings (e.g., U-V, V-W, W-U) at the motor terminals; an open circuit on one phase (e.g., U-V infinite, U-W infinite) indicates an internal motor fault.
- 4
If a motor contactor is used, check its contacts for continuity across phase A (e.g., terminals 1-2) with the contactor energized and de-energized.
- 5
Temporarily swap the motor phase A and B connections at the drive (connect motor Phase A cable to drive V, motor Phase B cable to drive U) and observe if the fault shifts to 'Wire break in phase B'.