Common Fault Codes of Servo Drive on NCF Coil Feeder

Our NCF series metal strip servo feeders adop Yaskawa servo motors and servo drives. This article is to introduce the common fault codes on Yaskawa servo drive. The NCF series roller feeders are for feeding coil thickness less than 4.5mm and width less than 1300mm. They can work with press machines to be automatic stamping line.

Key Troubleshooting Guidelines

Check External First‌: Over 80% of faults stem from wiring, power supply, or mechanical issues — not internal drive failure.

Refer to Manuals‌: Consult official Yaskawa documents such as:

Sigma-7 Troubleshooting Manual (SIEPS800002)

G5/E7/F7 Drive Technical Manuals (TM4515, TM.E7.01)

Use Diagnostic Tools‌: Leverage software like ‌MotionWorks IEC‌ or ‌DriveWorksEZ‌ for parameter backup, monitoring, and fault history analysis.

Enable Communication‌: For ‌CPF01 COM-ERR(OP&INV)‌, reseat the digital operator, check cable integrity, or replace control board if needed .

Encoder Best Practices‌: Replace absolute encoder batteries every 2–5 years to prevent data loss during power-off.

Common Yaskawa Servo Drive Fault Codes & Corrective Actions

| Fault Code | Fault Name (English) | Description | Possible Causes | Corrective Actions |

| --- | --- | --- | --- | --- |

| ‌A.00‌ | Absolute Data Error | Failed to receive or verify absolute encoder data | Encoder power loss, loose wiring, mismatched encoder type | Check encoder power (+5V, battery); reinitialize absolute data; replace encoder if faulty |

| ‌A.02‌ | Parameter Interrupt | User parameters not detected or corrupted | EEPROM failure, parameter reset required | Restore factory defaults; re-enter parameters via teach pendant or software |

| ‌A.04‌ | Parameter Setting Error | Parameter value exceeds allowable range | Manual input error, invalid configuration | Review parameter manual; correct settings (e.g., Cn-1E, Cn-1F) |

| ‌A.10‌ | Overcurrent | Excessive current in motor or drive output | Motor short circuit, mechanical jam, rapid acceleration | Test motor insulation; remove load blockage; extend acceleration time; inspect IGBT module |

| ‌A.30‌ | Regenerative Circuit Check Error | Regenerative resistor open/short or not connected | Damaged brake resistor, faulty transistor | Measure P-B resistance; replace resistor or regenerative unit |

| ‌A.31‌ | Position Error Pulse Overflow | Position command exceeds Cn-1E setting | Incorrect pulse input, encoder resolution mismatch | Increase Cn-1E value; check encoder feedback integrity |

| ‌A.40‌ | Main Circuit Voltage Error (Overvoltage) | DC bus voltage too high | High supply voltage, poor regeneration | Check input voltage; install external regenerative resistor; verify brake chopper function |

| ‌A.41‌ | Main Circuit Voltage Error (Undervoltage) | DC bus voltage too low | Low supply voltage, phase loss | Measure three-phase voltage; check for loose connections or blown fuses |

| ‌A.51‌ | Overspeed | Motor speed exceeds detection threshold | Faulty speed reference, encoder noise | Inspect speed command signal; shield encoder cables; adjust speed loop gain |

| ‌A.71‌ | Overload (Large Load) | Motor exceeds rated torque for seconds | Heavy load, transmission jam | Reduce load; check mechanical alignment; confirm motor-drive compatibility |

| ‌A.72‌ | Overload (Small Load) | Continuous overload operation | Sustained high torque demand | Optimize duty cycle; improve cooling; check for overheating |

| ‌A.80‌ | Absolute Encoder Pulse Error | Encoder pulses per revolution mismatch | Wiring fault, encoder model mismatch | Recheck encoder connection; confirm encoder type compatibility |

| ‌A.81‌ | Absolute Encoder Failure | Encoder power (+5V/battery) lost | Dead battery, power circuit failure | Replace encoder battery; check power supply lines |

| ‌A.82‌ | Absolute Encoder Checksum Error | Encoder memory checksum failure | Data corruption, EMI interference | Reinitialize encoder data; replace encoder if persistent |

| ‌A.83‌ | Absolute Encoder Battery Error | Battery voltage below threshold | Low battery, long-term power-off | Replace 3V lithium battery; avoid extended power loss |

| ‌A.84‌ | Absolute Encoder Data Error | Received encoder data invalid | Signal interference, cable damage | Use shielded cable; replace encoder cable; verify communication settings |

| ‌A.85‌ | Absolute Encoder Overspeed | Encoder powered at >400 rpm | High-speed startup without delay | Adjust startup sequence; ensure encoder initializes before motion |

| ‌A.A1‌ | Overheat | Drive heatsink temperature too high | Poor ventilation, fan failure | Clean heatsink; check fan operation; improve cabinet airflow |

| ‌A.B1‌ | Command Input Error | CPU cannot detect speed/position command | Open signal line, incorrect voltage level | Inspect +10V, pulse/direction signals; verify wiring continuity |

| ‌CPF00‌ | Handheld Unit Transmission Error 1 | No communication within 5 seconds of power-on | Loose connection, dead teach pendant battery | Reconnect operator; replace battery; cycle power |

| ‌A.F1‌ | Phase Loss | One phase missing in main power | Blown fuse, contactor failure | Measure L1-L2-L3 voltages; replace faulty component |