Mitsubishi FR-D700 Drive

Mitsubishi FR-D700 Drive Fault Codes:

Fault Code and Meaning	Cause and Remedy
HOLD Operation panel lock	Cause: Operation has been attempted during the operation panel lock. Remedy: Press MODE for 2s to release the lock.
LOCd Password locked	Cause: Reading/writing of a password-restricted parameter has been attempted. Remedy: Enter the password in Pr. 297 (Password lock/unlock) to unlock the password function before operating.
Er1 Write disable error	Cause: Parameter setting has been attempted although parameter writing is set to be disabled. Overlapping range has been set for the frequency jump. PU and the inverter cannot make normal communication. Remedy: Check the setting of Pr. 77 (Parameter write selection). Check the settings of Pr. 31 to Pr. 36 (frequency jump). Check the connection of PU and the inverter.
Er2 Write error during operation	Cause: Parameter writing has been attempted while a value other than “2” is set in Pr. 77 and the STF (STR) is ON. Remedy: Set “2” in Pr. 77 (Parameter write selection). After stopping the operation, set parameters.
Er3 Calibration error	Cause: Analog input bias and gain calibration values have been set too close. Remedy: Check the settings of calibration parameters C3, C4, C6 and C7.
Er4 Mode designation error	Cause: Parameter setting attempted in External/NET mode when Pr. 77 is not “2”. Parameter writing attempted when command source is not operation panel. Remedy: Set operation mode to “PU operation mode”. Set “2” in Pr. 77. Disconnect PU, set Pr. 551 = “9999”. Set Pr. 551 = “4”.
Err. Inverter reset	Cause: The reset signal (RES signal) is ON (Inverter output is shutoff). Remedy: Turn OFF the reset command.
OL Stall prevention (overcurrent)	Cause: The overcurrent stall prevention has been activated. Remedy: Increase/decrease Pr. 0 Torque boost by 1%. Set larger value in Pr. 7 Accel time and Pr. 8 Decel time. Reduce load weight. Try General-purpose magnetic flux vector control. Adjust Pr. 13 Starting frequency. Change Pr. 14 Load pattern. Adjust Pr. 22 Stall prevention level.
oL Stall prevention (overvoltage)	Cause: The overvoltage stall prevention function has been activated. Remedy: Set the deceleration time longer.
rb Regenerative brake pre-alarm	Cause: The regenerative brake duty has reached 85% of the Pr. 70 setting or higher. Remedy: Set the deceleration time longer. Check Pr. 30 and Pr. 70 settings.
TH Electronic thermal relay pre-alarm	Cause: The cumulative value of the electronic thermal O/L relay has reached 85% of the Pr. 9 setting. Remedy: Reduce the load and frequency of operation. Set an appropriate value in Pr. 9.
PS PU stop	Cause: STOP/RESET on the operation panel has been pressed during External operation. Remedy: Turn the start signal OFF and release with PU/EXT.
MT Maintenance signal output	Cause: The cumulative energization time has exceeded the maintenance output timer set value. Remedy: Setting “0” in Pr. 503 Maintenance timer erases the signal.
Uu Undervoltage	Cause: The voltage at the main circuit power has been lowered. Remedy: Investigate the devices on the power supply line such as the power supply itself.
SA Safety stop	Cause: Safety stop function activating (Outputs are being shut off). Remedy: Short across terminals S1-SC and S2-SC if not using safety stop. Check wiring of S1, S2, and SC. Contact sales representative if wiring has no fault.
Fn Fan alarm	Cause: The cooling fan is at a standstill although it is required to be operated. Remedy: Check for fan failure. Please contact your sales representative.
E.OC1 Overcurrent trip during acceleration	Cause: Overcurrent has occurred during acceleration. Remedy: Set acceleration time longer. Disconnect motor and restart; if fault persists, inverter may be faulty. Check wiring for short circuit/ground fault. Set Pr. 3 Base frequency to 50Hz (if motor is 50Hz). Lower stall prevention level. Activate stall prevention (Pr. 156).
E.OC2 Overcurrent trip during constant speed	Cause: Overcurrent has occurred during constant speed operation. Remedy: Keep load stable. Check wiring for shorts/ground faults. Lower stall prevention level.
E.OC3 Overcurrent trip during deceleration or stop	Cause: Overcurrent has occurred during deceleration or at a stop. Remedy: Set deceleration time longer. Check wiring for shorts/ground faults. Check mechanical brake timing. Lower stall prevention level.
E.OV1 Regenerative overvoltage trip during acceleration	Cause: Overvoltage has occurred during acceleration. Remedy: Set acceleration time shorter. Use regeneration avoidance function (Pr. 882, etc). Set Pr. 22 Stall prevention correctly. Set Pr. 154 = “11”.
E.OV2 Regenerative overvoltage trip during constant speed	Cause: Overvoltage has occurred during constant speed operation. Remedy: Keep load stable. Use regeneration avoidance function. Use brake resistor/unit/converter. Set Pr. 154 = “11”.
E.OV3 Regenerative overvoltage trip during deceleration	Cause: Overvoltage has occurred during deceleration or at a stop. Remedy: Set deceleration time longer. Make brake cycle longer. Use regeneration avoidance function. Use brake resistor/unit. Set Pr. 154 = “11”.
E.THT Inverter overload trip	Cause: The electronic thermal relay function for inverter element protection has been activated. Remedy: Set acceleration/deceleration time longer. Adjust Pr. 0 Torque boost. Adjust Pr. 14 Load pattern. Reduce the load.
E.THM Motor overload trip	Cause: The electronic thermal relay function for motor protection has been activated. Remedy: Reduce the load. For constant-torque motor, set Pr. 71. Set stall prevention level accordingly.
E.FIN Heatsink overheat	Cause: The heatsink has overheated. Remedy: Set surrounding air temperature within specifications. Clean the heatsink. Replace cooling fan.
E.ILF Input phase loss	Cause: One of the three phases on the inverter input side has been lost or largely unbalanced. Remedy: Wire cables properly. Repair cable breaks. Check Pr. 872 setting.
E.OLT Stall prevention stop	Cause: The output frequency has dropped to 1Hz due to excess motor load deceleration. Remedy: Reduce the load. (Check Pr. 22).
E.BE Brake transistor alarm detection	Cause: A fault has occurred in the brake circuit (e.g., transistor breakage). Remedy: Replace the inverter.
E.GF Output side earth fault overcurrent at start	Cause: An earth (ground) fault occurred on the inverter’s output side. Remedy: Remedy the ground fault portion.
E.LF Output phase loss	Cause: One of the three phases (U, V, W) on the inverter’s output side has been lost. Remedy: Wire cables properly. Check if motor capacity matches inverter.
E.OHT External thermal relay operation	Cause: The external thermal relay connected to the OH signal has been activated. Remedy: Reduce load and operate less frequently. Reset the inverter.
E.PTC PTC thermistor operation	Cause: Resistance of the PTC thermistor reached the protection level. Remedy: Reduce the load.
E.PE Parameter storage device fault	Cause: Operation of the component where parameters are stored has become abnormal. Remedy: Contact sales representative. If writing frequently, set Pr. 342 = “1” (RAM write).
E.PUE PU disconnection	Cause: Communication error between PU and inverter, or interval exceeded. Remedy: Connect PU cable securely. Check communication settings. Increase Pr. 122 interval or set to “9999”.
E.RET Retry count excess	Cause: Operation restart within the set number of retries has failed. Remedy: Eliminate the cause of the error preceding this indication.
E.CPU CPU fault	Cause: An error has occurred in the CPU and in the peripheral circuits. Remedy: Take measures against electrical noise. If persists, contact sales representative.
E.CDO Output current detection value exceeded	Cause: Output current has exceeded the output current detection level. Remedy: Check settings of Pr. 150, Pr. 151, Pr. 166, Pr. 167.
E.IOH Inrush current limit circuit fault	Cause: The resistor of the inrush current limit circuit has overheated. Remedy: Configure a circuit where frequent power ON/OFF is not repeated.
E.AIE Analog input fault	Cause: Voltage/Current input mismatch on Terminal 4 vs Pr. 267 setting. Remedy: Give frequency command by current input OR set Pr. 267 and switch to voltage correctly.
E.SAF Safety circuit fault	Cause: While safety circuit fault is occurring, terminals across S1/PC or S2/PC are opened. Remedy: Short terminals S1-SC and S2-SC if not using safety stop. Check wiring of S1, S2, SC and safety relay module.