Motor Will Not Run:
- Check for power at terminals L1(L), L2, and L3(N) for three-phase units or L1(L) and L3(N) for single-phase units. Apply power if necessary, and ensure input voltage is correct and terminal screws are secure.
- Check for voltage on output terminals T1, T2, and T3 to the motor. If necessary, turn the power off and then on again.
- Ensure there is no overload causing the motor to stall. Reduce the load if necessary.
- Check for any wiring problems and correct them.
- Verify that there is a forward or reverse run command and that the operational mode is correct. Operate the inverter through the digital keypad if necessary.

    Motor Runs in Wrong Direction:
- Ensure the wiring for output terminals T1, T2, and T3 matches the U, V, and W terminals of the motor.
- Check the wiring for the forward and reverse signals and correct if necessary.

    Motor Speed Cannot be Regulated:
- Verify that the signal wiring for the analog input frequency is correct.
- Check that the operation mode setting is correct. Use the keypad to verify.
- Ensure the load on the motor is not too excessive. Reduce the load if necessary.

    Motor Speed Too High or Too Low:
- Confirm that the motor specifications (poles, voltage, etc.) are correct.
- Verify that the gear ratio is correct.
- Check that the maximum output frequency setting is correct.

    Motor Speed Varies Erratically:
- Reduce the load if it is too excessive.
- Minimize the variation of the load and increase the capacities of the inverter and motor if necessary.
- Ensure the input power is not erratic and that there is no phase loss occurring. Add an AC reactor at the power input side if using single-phase power, and check the wiring if using three-phase power.

CPF (Program Problem): This error indicates a problem with the VFD's programming, possibly due to external noise interference (EMI). To resolve this, you can connect a parallel RC suppressor across the coil of the magnetic contactor causing the interference.

EPR (EEPROM Problem): This error suggests a faulty EEPROM (Electrically Erasable Programmable Read-Only Memory). The solution is to replace the EEPROM.

*-OV- (Overvoltage While Stopped): This error occurs when there's an overvoltage detected while the VFD is stopped, possibly due to a malfunctioning voltage detection circuit. You may need to repair or replace the unit.

*-LV- (Undervoltage While Stopped): This error indicates an undervoltage situation while the VFD is stopped. It could be due to low input voltage, a burned-out power resistor or fuse, or a detection circuit malfunction. Verify the input voltage, replace the power resistor or fuse, or repair/replace the inverter as needed.

*-OH- (Inverter Overheats While Stopped): This error signifies that the inverter is overheating while stopped, possibly due to a detection circuit malfunction or inadequate ventilation. You might need to replace or return the inverter and improve ventilation conditions.

CTER (Current Transducer Detection Error): This error indicates an issue with the current transducer or its circuit. The unit may need to be repaired or replaced.

OC-S (Overcurrent at Start): This error indicates an overcurrent condition at startup, possibly due to a motor winding and frame short circuit, a motor and ground short circuit, or a damaged power module. To resolve this, inspect the motor, check the wiring, and replace the power module if necessary.

OC-D (Overcurrent at Deceleration): This error occurs when the preset deceleration time is too short. You can set a longer deceleration time using Parameter b0008 to resolve this issue.

OC-A (Overcurrent at Acceleration): This error indicates an overcurrent condition during acceleration, which can be caused by a too short acceleration time, the motor's capacity exceeding the inverter's capacity, a short circuit between the motor winding and frame, a short circuit between motor wiring and ground, or a damaged IGBT module. To resolve this, set a longer acceleration time (Parameter b0007), replace the inverter with one that matches or exceeds the motor's capacity, check the motor and wiring, and replace the IGBT module if necessary.

OC-C (Overcurrent during Run): This error signifies an overcurrent condition during operation, possibly due to transient load or power changes. To address this, increase the inverter's capacity, repeat parameter auto-tuning (A006 = 1), or reduce stator resistance (A168) if the above actions are ineffective.

OV-C (Overvoltage during Operation/Deceleration): This error indicates an overvoltage condition during operation or deceleration, which can be caused by too short a deceleration time setting, excessive load inertia, or widely fluctuating input voltage. To resolve this, set a longer deceleration time, add a braking resistor or braking unit, add a reactor to the input line side, or increase the inverter's capacity.

Err4 (Illegal Interrupt of CPU): This error suggests an illegal interrupt of the CPU, possibly due to outside noise interference. If this occurs frequently, you may need to return the unit.

OVSP (Over Speed during Operation): This error indicates that the motor is operating at an excessive speed, which can be due to an excessive motor load, a small inverter capacity, a motor parameter error in vector mode, excessive gain in vector mode, or a fault in the current detection circuit. To resolve this, increase the acceleration/deceleration time (Parameters b007/b008), check and correct the motor parameter, adjust the stator resistance gain and rotor resistance gain (Parameters A168/A169, suggesting an incremental decrease of 50-100), or return the unit if necessary.

OC (Over-current during Stop): This error indicates an over-current condition during the stopping process, which can be due to a malfunction in the OC detection circuit or a bad connection for the CT signal cable. The recommended action is to send the inverter back for repair.

OL1 (Motor Overload): This error signifies that the motor is overloaded, which can be due to the motor being undersized or improper settings for Parameters A002 and A119-A122. To resolve this, increase the motor capacity or adjust the parameters accordingly.

OL2 (Inverter Overload): This error indicates that the inverter is overloaded due to an excessive load. The recommended action is to increase the inverter capacity.

OL3 (Over Torque): This error suggests that there is an excessive load or improper settings of parameters A125 and A126, resulting in over torque. To resolve this, increase the inverter capacity or adjust the parameters accordingly.

LVC (Undervoltage during Operation): This error occurs when the input voltage is too low, varies widely, or there is a main circuit relay error. To address this, improve the input voltage quality, set a longer acceleration time (Parameter b0007), add a line reactor to the input side, or send the inverter back for repair.

OH-C (Heat-sink Temperature too High during Operation): This error indicates that the heat-sink temperature is too high during operation, which can be due to an excessive load, high ambient temperature, or poor ventilation. To resolve this, check the load, increase the inverter capacity, or improve ventilation conditions.

STPO (Zero Speed Stop): This error occurs when the set frequency is less than 0.1Hz, indicating a zero-speed stop condition. The recommended action is to increase the set frequency.

STP1 (Fail to Direct Start on Power Up): This error signifies a failure to directly start the inverter on power-up, which can occur if the inverter is set for external terminal control mode and direct start on power up is disabled. To resolve this, set A017 = 0001 for direct start.

STP2 (Keypad emergency stop): The inverter stops and flashes STP2 when the Stop key is pressed while in external control mode or communication mode. To restart, turn the run switch off and then on again, or send a Stop and then a Run command from the PLC or PC.

E.S. (External emergency stop): The inverter decelerates to a stop and flashes E.S. when an external emergency stop signal is received through the control input terminals.

b.b. (External base block): The inverter stops immediately (motor coasts to stop) and then flashes b.b. when an external base block signal is input through the multi-functional input terminal.

ATER (Auto-tuning faults): Auto-tuning faults occur due to motor data errors or stopping the inverter during auto-tuning before completion.

PDER (PID feedback signal loss): PID feedback signal circuit error detection.

LOC (Parameter and frequency reverse modifications locked out): This error occurs when there's an attempt to modify the frequency parameter while A039 > 0000 or to reverse while b002 = 0001. To remedy, set A039 = 0000 and b002 = 0000.

Err1 (Keypad operation error): This error occurs when attempting to press the ▲ or ▼ keys when b004 > 0 or in speed operation, or when trying to modify parameters that cannot be modified during Run. To remedy, ensure b004 = 0 and modify parameters only in stop mode.

Err2 (Parameter setting error): This error occurs when the setting of b006 is within the ranges of parameters A032 ± A035 or A033 ± A035 or A034 ± A035, or when b005 ≤ b006. To remedy, modify the relevant parameters.

Err5 (Modification of parameter is not allowed during communication): This error occurs when attempting to enable command disabled during communication or when modifying parameters A164 -167 during communication. To remedy, issue an enable command before/while communicating and set parameters 164-167 before communicating.

Err6 (Communication failure): This error occurs due to faulty/incorrect wiring, incorrect settings of communication parameters, checksum error, or incorrect communication verification. To remedy, check hardware and wiring, and check parameters A161 – A164.

Err7 (Incorrect parameter settings): This error occurs when attempting to change A175 or when voltage and current detection circuits are malfunctioning. To remedy, reset the inverter or contact technical support.

EPr1 (Parameter set error, Copy unit failed): This error occurs when there is a connection issue with the Copy unit, Copy unit failure, or the HP rating on the Copy unit and the inverter are different. To remedy, modify parameter A040, change the copy unit, and ensure the HP rating is the same.

EPr2 (Parameters do not match): This error occurs when copying parameters to the inverter to verify that the parameters do not match. To remedy, change the copy unit if the voltage and HP rating of the Copy unit are different from the inverter.