Technical support – Delta VFD fault codes
If a fault code appears on the drive display, use the tables below to identify the code and the recommended corrective action. If the fault persists or its cause is unclear, contact us for on-site diagnostics.
Delta VFD-EL-W fault codes
| Code | Fault | Recommended action |
|---|---|---|
| oc | Overcurrent | Check the wiring between the motor and drive for short circuits and verify the load. Increase the acceleration time. |
| ov | Overvoltage | Check the input voltage. Increase the deceleration time or use a braking resistor. |
| oH1 | Overheating | Check the ventilation openings and ambient temperature. |
| Lv | Low voltage | Check the input voltage and phases. |
| oL | Overload | Check the motor load. Use a higher-rated drive if necessary. |
| oL1 | Electronic thermal overload | Reduce the output current and check the settings. |
| oL2 | Motor overload | Reduce the motor load. |
| EF | External fault | Reset the drive after the external fault signal has cleared. |
| ocA | Overcurrent during acceleration | Increase the acceleration time and reduce torque compensation. |
| ocd | Overcurrent during deceleration | Increase the deceleration time. |
| ocn | Overcurrent at constant speed | Check the insulation and whether the motor is stalled. |
| HL | Phase loss | Check the incoming three-phase supply. |
| cFA | Automatic acceleration/deceleration fault | Check the motor and regenerative energy. |
| AErr | Analog signal fault | Check the ACI wiring. |
| PTC1 | Internal motor overheating | Check cooling, load and the rated-current setting. |
| FbE | PID feedback fault | Check parameter Pr.10.01 and the AVI/ACI wiring. |
| dEv | PID feedback deviation | Check the PID feedback wiring and parameters. |
| HotP | Thermal fuse trip | Check the thermal load and parameter Pr.06.17. |
| bb | External base block | The fault clears automatically after the BB signal is removed. |
| cE | Communication fault | Check the RJ45 wiring and communication protocol settings. |
| cF1.0 | EEPROM write fault | Return the unit for service. |
| cF2.0 | EEPROM read fault | Reset the drive; if the fault persists, return the unit for service. |
| HPF1–HPF4 | Hardware fault | Return the unit for service. |
| cF3.x | Wiring detection fault | Return the unit for service. |
Delta VFD-MS300 fault codes
| Code | Fault | Recommended action |
|---|---|---|
| ocA | Overcurrent during acceleration | Increase the acceleration time and check the wiring. |
| ocd | Overcurrent during deceleration | Increase the deceleration time. |
| ocn | Overcurrent at constant speed | Check the insulation and whether the motor is stalled. |
| GF | Ground fault | Check the insulation of the motor and cable. |
| ocS | Overcurrent during stop | Check the wiring. |
| ov / ovd / ovn / ovS | Overvoltage | Increase the deceleration time or use a braking resistor. |
| LvA / Lvd / Lvn / LvS | Low voltage | Check the input voltage and phases. |
| OrP | Input phase loss | Check the incoming three-phase supply. |
| oH1 | IGBT overheating | Check ventilation and ambient temperature. |
| oL | Overload | Reduce the load or use a higher-rated drive. |
| oL1 / EoL2 | Electronic thermal protection | Check the motor-current setting. |
| oH3 | Motor overheating (PTC/PT100) | Check motor cooling and load. |
| ot1 / ot2 | Overtorque | Check the load and torque-detection settings. |
| uC | Underload | Check the motor wiring and load. |
| cF2 | EEPROM read fault | Reset the drive; if the fault persists, service is required. |
| AUE | Auto-tuning fault | Check the motor data and wiring. |
| EF | External fault | Reset the drive after clearing the external fault signal. |
| EF1 | Emergency stop | Reset the drive after clearing the emergency-stop signal. |
| bb | External base block | The fault clears automatically after the BB signal is removed. |
| STO | STO active | Check the STO wiring and signal. |
| STL1 / STL2 / STL3 | STO signal loss | Check the STO cable and connector. |
| OPHL | Output phase loss | Check the motor wiring (U/V/W). |
| CE1–CE10 | Communication fault | Check the Modbus wiring and protocol. |
Delta VFD-C2000plus fault codes
| Code | Fault | Recommended action |
|---|---|---|
| ocA / ocd / ocn / ocS | Overcurrent | Check the wiring and increase the acceleration or deceleration time. |
| GF | Ground fault | Check the insulation of the motor and cable. |
| occ | IGBT short circuit | Service is required. |
| ovA / ovd / ovn / ovS | Overvoltage | Increase the deceleration time and use a braking resistor if necessary. |
| LvA / Lvd / Lvn / LvS | Low voltage | Check the input voltage. |
| OrP | Input phase loss | Check the three-phase supply. |
| oH1 | IGBT overheating | Check ventilation. |
| oH2 | Internal component overheating | Check ventilation and load. |
| oL / EoL1 / EoL2 | Overload | Reduce the load. |
| oH3 | Motor overheating | Check motor cooling. |
| ot1 / ot2 / ot3 / ot4 | Overtorque | Check the load. |
| uC | Underload | Check the motor wiring. |
| AUE / AUE1–AUE5 | Auto-tuning fault | Check the motor data. |
| EF / EF1 | External fault / Emergency stop | Reset the drive after clearing the signal. |
| bb | External base block | The fault clears automatically. |
| STO / STL1 / STL2 / STL3 | STO fault | Check the STO wiring. |
| OPHL | Output phase loss (U/V/W) | Check the motor wiring. |
| CE1–CE10 | Modbus communication fault | Check the wiring and protocol. |
| bF | Brake transistor fault | Check the braking resistor. |
| ydc | Star-delta switching fault | Check the switching contactors. |
| dEb | Deceleration energy backup fault | Check the DC-bus voltage. |
On-site diagnostics and repair
If the problem persists after identifying the fault code, or the cause is unclear, contact us for on-site diagnostics. We provide variable-frequency drive replacement, commissioning and on-site troubleshooting.
Phone: +36 20 201 6263