Inovance MD500E Drive Fault Codes List

A comprehensive guide to Inovance MD500E drive fault codes. Learn to interpret Err codes, troubleshoot plastic machinery/engineering applications, and use InoDriveShop.

Inovance MD500E Fault Codes Reference Table

Below is the complete list of fault codes, descriptions, and potential solutions associated with the MD500E series.

Fault Codes	Cause & Solution
Err02 Overcurrent during acceleration	Cause & Solution: 1. Ground fault or short circuit exists in the output circuit. - Check whether short-circuit occurs on the motor, the motor cable or contactor. 2. Acceleration time is too short. - Increase acceleration time. 3. Customized torque boost or V/F curve is not appropriate. - Adjust the customized torque boost or V/F curve. 4. The voltage is too low. - Adjust the voltage to normal range. 5. The spinning motor is started. - Enable the catching a spinning motor function or start the motor after it stops. 6. A load is applied suddenly during acceleration. - Cancel the suddenly added load. 7. The rated AC drive power is low. - Replace the drive by one with higher rated power. 8. The braking resistor resistance is small. - The braking resistor is short circuited. - Replace a new braking resistor.
Err03 Overcurrent during deceleration	Cause & Solution: 1. Ground fault or short circuit exists in the output circuit. - Check whether short-circuit occurs on motor, motor cable or contactor. 2. Acceleration time is too short. - Increase acceleration time. 3. The voltage is too low. - Adjust the voltage to normal range. 4. A load is added suddenly during deceleration. - Cancel the suddenly added load. 5. Braking unit and braking resistor are not installed. - Install the braking unit and braking resistor. 6. The braking resistor resistance is small or the braking resistor is short circuited. - Replace a new braking resistor.
Err04 Overcurrent at constant speed	Cause & Solution: 1. Ground fault or short circuit exists in the output circuit. - Check whether short-circuit occurs on the motor, motor cable or contactor 2. The voltage is too low. - Adjust the voltage to normal range. 3. A load is added suddenly during running. - Cancel the suddenly added load. 4. The rated AC drive power is low. - Replace the drive by one with higher rated power. 5. The braking resistor resistance is small or the braking resistor is short circuited. - Replace a new braking resistor.
Err05 Overvoltage during acceleration	Cause & Solution: 1. Input voltage is too high. - Adjust input voltage to normal range. 2. An external force drives motor during acceleration. - Cancel the external force. 3. Braking unit and braking resistor are not installed. - Install the braking unit and braking resistor. 4. Acceleration time is too short. - Increase acceleration time.
Err06 Overvoltage during deceleration	Cause & Solution: 1. Input voltage is too high. - Adjust input voltage to normal range. 2. An external force drives motor during deceleration. - Cancel the external force or install the braking resistor. 3. Deceleration time is too short. - Increase deceleration time. 4. Braking unit and braking resistor are not installed. - Install the braking unit and braking resistor.
Err07 Overvoltage at constant speed	Cause & Solution: 1. Input voltage is too high. - Adjust input voltage to normal range. 2. An external force drives motor during running. - Cancel the external force or install a braking resistor.
Err08 Pre-charge resistor fault	Cause: Bus voltage fluctuates around undervoltage threshold continuously Solution: There is an hardware or software issue in drive. Need to repair or replace drive.
E09.00 Undervoltage	Cause & Solution: 1. An instantaneous power failure occurs. - Reset the fault 2. The AC drive's input voltage is not within the permissible range. - Adjust the voltage to normal range. 3. The bus voltage is abnormal. - Replace the AC drive. 4. The rectifier bridge, the pre-charge resistor, the drive board or the control board are abnormal. - Replace the AC drive.
Err10 Drive overload	Cause & Solution: 1. The load is too heavy or locked-rotor occurs on the motor. - Reduce the load or check motor and mechanical conditions. 2. The rated AC drive power is low. - Replace the drive by one with higher rated power.
Err11 Motor overload	Cause & Solution: 1. F9-01 (Motor overload protection gain) is set improperly. - Set F9-01 correctly. 2. The load is too heavy or locked-rotor occurs on the motor. - Reduce the load or check motor and mechanical conditions. 3. The rated AC drive power is low. - Replace the drive by one with higher rated power.
Err12 Input phase loss	Cause & Solution: 1. Three phase input is abnormal. - Eliminate faults in external circuitry 2. Drive board is abnormal. - Eliminate faults in external circuitry 3. Lightning protection board is abnormal. - There is an hardware or software issue in drive. Need to repair or replace drive. 4. Control board is abnormal. - There is an hardware or software issue in drive. Need to repair or replace drive.
Err13 Output phase loss	Cause & Solution: 1. Motor winding is damaged. Check resistance between motor cables. - Replace motor is winding is damaged. 2. The cable connecting the AC drive and the motor is abnormal. - Check for wiring errors and ensure the output cable is connected properly 3. The AC drive's three-phase outputs are unbalanced when the motor is running. - Check whether the motor three-phase winding is normal. 4. The drive board or the IGBT is abnormal. - Replace the AC drive.
Err14 IGBT overheat	Cause & Solution: 1. The ambient temperature is too high. - Lower the ambient temperature. 2. The ventilation is clogged. - Clean the ventilation. 3. The fan is damaged. - Replace the cooling fan. 4. The thermally sensitive resistor of IGBT is damaged. - Replace the AC drive. 5. The AC drive IGBT is damaged. - Replace the AC drive.
Err15 External equipment fault	Cause & Solution: 1. External fault signal is input via DI. - Confirm that the mechanical condition allows restart (F8-18) and reset the operation. 2. External fault signal is input via virtual I/O. - Confirm that the virtual I/O parameters in group A1 are set correctly and reset the operation.
Err16 Communication fault	Cause & Solution: 1. The host controller is in abnormal state. - Check the cable of the host controller. 2. Communication cable is abnormal. - Check the communication cables. 3. Communication parameters in group Fd are set improperly. - Set communication parameters in group Fd properly. 4. After all the preceding checkings are done but the fault still exists, restore the default settings.
Err17 Contactor fault	Cause & Solution: 1. Drive board and power supply are abnormal. - Replace drive board or power supply board. 2. Contactor is abnormal. - Replace contactor. 3. The lightning protection board is abnormal. - Replace the lightning protection board.
Err18 Current detection fault	Cause: The drive board is abnormal. Solution: There is an hardware or software issue in drive. Need to repair or replace drive.
Err19 Motor auto-tuning fault	Cause & Solution: 1. Motor parameters are not set according to nameplate. - Set motor parameters correctly according to nameplate. 2. Motor auto-tuning times out. - Check the cable connecting AC drive and motor. 3. The encoder is abnormal. - Check whether F1-27 (encoder pulses per revolution) is set correctly. - Check whether signal lines of encoder are connected correctly and securely.
Err20 Encoder fault	Cause & Solution: 1. Encoder is not matched. - Set the type of encoder correctly. 2. Encoder wiring is incorrect.  Check the PG card power supply and phase sequence. 3. Encoder is damaged. - Replace encoder. 4. PG card is abnormal. - Replace PG card.
Err21 EEPROM read- write fault	Cause: EEPROM chip is damaged. Solution: Replace the AC drive.
Err23 Short circuit to ground	Cause & Solution: 1. The motor is short circuited to the ground. - Replace cable or motor. 2. The upper IGBT is damaged. - There is an hardware or software issue in drive. Need to repair or replace drive.
Err26 Accumulative running time reached	Cause: Accumulative running time reaches the setting value. Solution: Clear the record through parameter initialization.
Err27 User-defined fault 1	Cause: User-defined fault 1 is input via DI. Solution: Reset the operation.
Err28 User-defined fault 2	Cause: User-defined fault 2 is input via DI. Solution: Reset the operation.
Err29 Accumulative power-on time reached	Cause: Accumulative power-on time reaches the setting value. Solution: Clear the record through parameter initialization.
Err30 Off load fault	Cause: The output current of AC drive is smaller than F9-64 (load loss detection level). Solution: Check whether the load is disconnected or the setting of F9-64 and F9-65 (load lost detection time) satisfies actual running conditions.
Err31 PID feedback lost during running	Cause: PID feedback is smaller than the setting value of FA-26 (detection level of PID feedback loss). Solution: Check PID feedback or set FA-26 properly.
Err40 Pulse-by- pulse current limit fault	Cause & Solution: 1. The load is too heavy or locked-rotor occurs on the motor. - Reduce the load or check motor and mechanical conditions. 2. The rated AC drive power is low. - Replace the drive by one with higher rated power.
Err41 Motor switchover fault during running	Cause: Motor switchover via terminal during drive running of the AC drive. Solution: Perform motor switchover after the AC drive stops.
Err42 Speed error	Cause & Solution: 1. Encoder parameters are set improperly. - Set encoder parameters properly. 2. Motor auto-tuning is not performed. - Perform motor auto-tuning. 3. F9-69 (detection level of speed error) and F9-70 (detection time of speed error) are set oncorrectly. - Set F9-69 and F9-70 correctly based on actual condition.
Err43 Motor overspeed	Cause & Solution: 1. Encoder parameters are set improperly. - Set encoder parameters properly. 2. Motor auto-tuning is not performed. - Perform motor auto-tuning. 3. F9-67 (Overspeed detection level) and F9-68 (Overspeed detection time) are set incorrectly. - Set F9-67 and F9-68 correctly based on the actual situation.
Err45 Motor overtemperature	Cause & Solution: 1. Cable connection of temperature sensor becomes loose - Check cable connection of temperature sensor. 2. The motor temperature is too high. - Decrease carrier frequency or take other measures to cool the motor.
Err61 Braking unit overload	Cause: Resistance of braking resistor is too small. Solution: Replace a braking resistor of larger resistance.
Err62 Short-circuit of braking circuit	Cause: Braking IGBT is abnormal. Solution: There is an hardware or software issue in drive. Need to repair or replace drive.
HC Fault	Cause & Solution: 1. The cable between the drive board and control board is in poor contact. - Re-connect the 4-pin cable and 28-pin cable. 2. The control board is damaged. - Replace the AC drive. 3. The motor or motor cable is short circuited to ground. - Check whether short-circuit occurs on motor, motor cable or contactor. 4. The mains voltage is too low. - Check the power supply.
Err51 Initial position angle identification fault	Cause & Solution: 1. AC drive output phase loss - Check whether the motor wiring is correct. 2. The AC drive current detection fails or the hall is damaged. - Check the hall. 3. The motor inductance is too large. - Set F9-75 to avoid this fault.
A64 Counter electromotive force identification exception warning	Cause & Solution: 1. Related parameters are set incorrectly. - Set related parameters correctly, the rated frequency and rotation speed in particular. 2. F1-20 is set incorrectly. - Check whether F1-20 is set to a too large or too small value. 3. Counter electromotive force identification exception during dynamic identification - Check whether the motor has no load during dynamic identification and whether the motor rotates at 40% of the rated rotation speed. - If the motor has load and its speed is below 40% of the rated rotation speed, perform identification again after disconnecting the motor from load. 4. The motor is demagnetized. - Check whether the motor is demagnetized. 5. Counter electromotive force is too large or too small. - If yes, press STOP to reset the warning and the motor continues to run.

 

How to Read MD500E Faults via InoDriveShop

Because the MD500E is often used in complex load applications (like injection molding), standard keypad diagnostics might not be enough. In 2026, using the InoDriveShop PC software is highly recommended.

• Snapshot Data: The MD500E records specific drive states at the moment of failure. Using the software or the U0 parameter group on the keypad, you can verify the Bus Voltage, Output Current, and Terminal Status at the exact instant the “Err” code was triggered.
• Cyclic Load Analysis: If your MD500E is powering plastic machinery, faults often occur during specific parts of the cycle (e.g., injection or clamping). The oscilloscope function in InoDriveShop allows you to map the fault against the machine cycle to identify if mechanical binding is causing an overload.
• Detailed Sub-Codes: For communication or hardware faults, the software can display sub-codes that are not visible on the 7-segment LED display, helping you distinguish between a wiring issue and an internal card failure.

Frequently Asked Questions (FAQ)

Q: What is the difference between an Alarm and a Fault?

A: An Alarm (typically displayed as ‘A’ or ‘ALm’ codes) indicates a potential issue—such as overload pre-warning—but allows the machine to finish its current cycle. A Fault (displayed as ‘Err’ codes) immediately shuts down the output to protect the drive components.

Q: How do I reset an Inovance MD500E fault?

A: You can reset the drive using the following methods:

1. Pressing the STOP/RESET button on the keypad.
2. Triggering a Digital Input (DI) terminal configured for the “Reset” function (Function 9).
3. Sending a reset command via the communication interface (Modbus/CANopen) if connected to a PLC.

Q: Where is the fault history stored?

A: The MD500E stores the last 3 fault codes in parameters U0-00 (latest), U0-01, and U0-02. Detailed electrical data regarding the most recent fault is stored in parameters U0-03 through U0-17.