Motor speed feedback
ABB · ACS880
¿Qué significa 7301 ?
No motor speed feedback signal is being received by the drive. This fault means the drive cannot accurately monitor motor speed, which is critical for closed-loop control and protection. The drive will likely trip or fail to start reliably, impacting performance and safety.
Causas comunes
- Encoder or resolver feedback cable damage (e.g., open circuit in signal lines, short to ground, poor shielding).
- Encoder/resolver malfunction (e.g., internal failure, loss of 5VDC or 15VDC power supply to the device).
- Incorrect wiring of feedback signals (e.g., A/B/Z signals swapped or connected to wrong terminals X20, X21).
- Loose or corroded terminals at the encoder, motor junction box, or drive's feedback connector (e.g., X20, X21).
- Excessive electromagnetic interference (EMI) on feedback cables without proper shielding and grounding.
Pasos de reparación & Lista de verificación
Haga clic en los pasos para seguir su progreso.
- 1
Verify 5VDC or 15VDC power supply to the encoder at the encoder connector (e.g., pins 1 and 2).
- 2
Check continuity of each signal wire (A, /A, B, /B, Z, /Z) from the encoder to the drive's feedback terminals (e.g., X20, X21).
- 3
Visually inspect the encoder or resolver for mechanical damage, contamination, or loose mounting on the motor shaft.
- 4
Confirm encoder parameters (e.g., P21-01 Encoder type, P21-02 Pulses per revolution) match the installed feedback device.
- 5
Ensure proper shielding of the feedback cable is connected to ground at the drive's shield clamp and at the motor frame.