Mitsubishi FR-F500J Drive

Mitsubishi FR-F500J Drive Fault Codes:

Fault Code and Meaning	Cause and Remedy
OC1 Overcurrent shut-off during acceleration	Cause: When the inverter output current reaches or exceeds approximately 150% of the rated inverter current during acceleration, the protective circuit is activated to stop the inverter output. Check points: Sudden acceleration, long downward acceleration time in vertical lift applications, or output short-circuit/ground fault. Remedy: Increase the acceleration time. Shorten the downward acceleration time in vertical lift application.
OC2 Overcurrent shut-off during constant speed	Cause: When the inverter output current reaches or exceeds approximately 150% of the rated inverter current during constant speed operation. Check points: Sudden load change or output short-circuit/ground fault. Remedy: Keep load stable.
OC3 Overcurrent shut-off during deceleration	Cause: When the inverter output current reaches or exceeds approximately 150% of the rated inverter current during deceleration. Check points: Sudden speed reduction, output short-circuit/ground fault, or too fast operation of the motor’s mechanical brake. Remedy: Increase the deceleration time. Adjust brake operation.
OV1 Regenerative overvoltage shut-off during acceleration	Cause: Main circuit DC voltage rises to specified value due to excessive regenerative energy or surge voltage during acceleration. Check points: Too slow acceleration (e.g. during downward acceleration in vertical lift load). Remedy: Decrease the acceleration time. Install a power factor improving reactor.
OV2 Regenerative overvoltage shut-off during constant speed	Cause: Main circuit DC voltage rises to specified value due to excessive regenerative energy or surge voltage during constant speed. Check points: Sudden load change. Remedy: Keep load stable. Install a power factor improving reactor.
OV3 Regenerative overvoltage shut-off during deceleration or stop	Cause: Main circuit DC voltage rises to specified value due to excessive regenerative energy or surge voltage during deceleration or stop. Check points: Sudden speed reduction. Remedy: Increase the deceleration time (match moment of inertia of load). Decrease the braking duty. Install a power factor improving reactor.
THM Motor overload shut-off (electronic thermal relay function)	Cause: Motor overheat due to overload or reduced cooling capability during low speed operation. (Note: If using multi-pole or multiple motors, use an external thermal relay). Check points: Check the motor for use under overload. Remedy: Reduce the load weight. For a constant-torque motor, set the constant-torque motor in Pr. 71 “applied motor”.
THT Inverter overload shut-off (electronic thermal relay function)	Cause: Current of more than 120% of rated output flows (but less than 150%) causing inverse time characteristics to activate to protect output transistors. Check points: Check the motor for use under overload. Remedy: Reduce the load weight.
FIN Fin overheat	Cause: Heatsink overheats and temperature sensor actuates. Check points: Too high ambient temperature or heatsink clogging. Remedy: Set the ambient temperature to within the specifications. Clean heatsink if clogged.
GF Start-time output side earth (ground) fault overcurrent	Cause: Earth (ground) fault current flows at start due to a fault on the output (load) side. Valid when Pr. 40 is set to “1”. Check points: Earth (ground) fault in the motor or connection cable. Remedy: Remedy the earth (ground) fault portion.
LF Output phase failure protection	Cause: One of the three phases (U, V, W) on the output side opens at motor start. Check points: Check wiring (ensure motor is normal). Check if motor used is smaller (two ranks or less) than inverter capacity. Remedy: Wire the cables properly. Set “0” (without output phase failure protection) in H8 if using a smaller motor.
OHT External thermal relay / OH Fault	Cause: External thermal relay or internally mounted motor temperature relay switches on (contacts open). Check points: Motor overheating. Check if Pr. 60 to Pr. 63 is set correctly to 7 (OH signal). Remedy: Reduce the load and operating duty.
OLT Stall prevention (overload)	Cause: Running frequency has fallen to 0 by stall prevention operation activated (OL appears). Check points: Check the motor for use under overload. Remedy: Reduce the load weight.
OPT Option Fault / Communication error	Cause: Setting error or connection fault during use of RS-485 communication function. Check points: Check that the connector is plugged securely. Remedy: Make connection securely. Please contact your sales representative.
PE (FR-PU04: Corrupt Memory) Parameter storage device alarm	Cause: A fault occurred in parameters stored (example: EEPROM fault). Check for too many number of parameter write times. Remedy: Please contact your sales representative.
PUE (FR-PU04: PU Leave Out) Parameter Unit disconnection	Cause: Stops the inverter output if communication between inverter and PU is suspended (e.g. if PU is disconnected with “1” set in parameter n17). Remedy: Fit the FR-PU04 securely.
RET (FR-PU04: Retry No Over) Retry count over	Cause: If operation cannot be resumed properly within the number of retries set, this function stops the inverter output. Remedy: Eliminate the cause of the error preceding this error indication.
CPU (FR-PU04: CPU Fault) CPU error	Cause: If the arithmetic operation of the built-in CPU does not end within a predetermined period, the inverter self-determines it as an alarm and stops output. Remedy: Please contact your sales representative.
FN Fan trouble	Cause: For the inverter which contains a cooling fan, this appears when the cooling fan stops due to a fault. Remedy: Replace the fan.
OL Stall prevention (overcurrent)	Cause: Current more than 120% of rated inverter current flows in the motor. During acceleration: Stops frequency increase. During constant speed: Lowers frequency. During deceleration: Stops frequency decrease. Check the motor for use under overload. Remedy: The acceleration/deceleration time may change. Increase the stall prevention operation level with Pr. 22. Disable stall prevention with Pr. 21. Check that the torque boost (Pr. 0) setting is not higher than required.
oL Stall prevention (overvoltage)	Cause: If the regenerative energy of the motor increases too much to exceed the brake capability, this function stops the decrease in frequency to prevent overvoltage shut-off. Check for sudden speed reduction. Remedy: The deceleration time may change. Increase the deceleration time using Pr. 8 “deceleration time”.
PS PU stop	Cause: Pr. 75 “reset selection/PU stop selection” had been set and a stop was made by pressing the STOP/RESET of the operation panel or parameter unit during external operation mode. Remedy: Refer to the manual page 116.
UV / F5J Undervoltage	Cause: Power supply voltage decreases (below about 150VAC for 200V class / 300VAC for 400V class). Check for a start of large-capacity motor. Check that the power supply capacity is sufficient. Remedy: Check the power supply system equipment such as the power supply.
Er1 (FR-PU04: Control Mode) Write disable error	Cause: Write was performed with “1” (write disable) set in Pr. 77. Frequency jump setting range overlapped. Parameter write was performed though the operation panel does not have the write precedence. Remedy: Check the setting of Pr. 77 “parameter write disable selection”. Check the settings of Pr. 31 to 36 (frequency jump). Check communication connector settings.
Er2 (FR-PU04: OPERATOR ERR) Write-while-running error / mode designation error	Cause: Write was performed during operation. An attempt was made to change Pr. 79 setting while run command is input. Write was performed in the external operation mode. Remedy: After stopping operation, make parameter setting. After setting the operation mode to the “PU operation mode”, make parameter setting.
Er3 (FR-PU04: Incr I/P) Calibration error	Cause: Analog input bias and gain calibration values are too close. Remedy: Check the settings of C3, C4, C6 and C7 (calibration functions).