Mitsubishi FR-F500 Drive

Fault Code and MeaningCause and Remedy
E.OC1

Overcurrent shut-off during acceleration

Cause: When inverter output current exceeds approx 150% during acceleration.

  • Check for sudden acceleration.

  • Check for long descending acceleration time (lift applications).

  • Check for output short circuit.

  • Check that main circuit power (R, S, T) is supplied.




Remedy:



  • Increase the acceleration time. (Decrease descending acceleration time for lift applications).

  • If “E.OC1” is always lit at start, disconnect motor and restart inverter. If still lit, contact sales representative.

  • Supply main circuit power.


E.OC2

Overcurrent shut-off during constant speed

Cause: When inverter output current exceeds approx 150% during constant speed.

  • Check for sudden load change.

  • Check for output short circuit.




Remedy:



  • Keep load stable.


E.OC3

Overcurrent shut-off during deceleration

Cause: When inverter output current exceeds approx 150% during deceleration.

  • Check for sudden speed reduction.

  • Check for output short circuit.

  • Check for too fast operation of motor’s mechanical brake.




Remedy:



  • Increase the deceleration time.

  • Check mechanical brake operation.


E.OV1

Regenerative overvoltage shut-off during acceleration

Cause: Regenerative energy or surge voltage caused internal DC voltage to exceed specified value.

  • Check for too slow acceleration (i.e. during descending acceleration with lifting load).




Remedy:



  • Decrease the acceleration time.


E.OV2

Regenerative overvoltage shut-off during constant speed

Cause: Regenerative energy or surge voltage caused internal DC voltage to exceed specified value.

  • Check for sudden load change.




Remedy:



  • Keep load stable.

  • Use the brake unit or power regeneration common converter (FR-CV) as required.


E.OV3

Regenerative overvoltage shut-off during deceleration or stop

Cause: Regenerative energy or surge voltage caused internal DC voltage to exceed specified value.

  • Check for sudden speed reduction.




Remedy:



  • Increase the deceleration time. (Set time matching inertia moment of load).

  • Decrease the braking duty.

  • Use the brake unit or power regeneration common converter (FR-CV) as required.


E.THM

Motor overload shut-off (electronic overcurrent protection)

Cause: Motor overheat due to overload or reduced cooling capability.

  • Check the motor for use under overload.




Remedy:



  • Reduce the load weight.

  • For a constant-torque motor, change the Pr. 71 setting to the constant-torque motor setting.


E.THT

Inverter overload shut-off (electronic overcurrent protection)

Cause: Current >120% rating flows (inverse-time characteristics activated).

  • Check the motor for use under overload.




Remedy:



  • Reduce the load weight.


E.IPF

Instantaneous power failure protection

Cause: Power failure occurred for longer than 15ms.

  • Find the cause of instantaneous power failure occurrence.




Remedy:



  • Remedy the instantaneous power failure.

  • Prepare a backup power supply for instantaneous power failure.

  • Set the function of automatic restart after instantaneous power failure.


E.UVT

Undervoltage protection

Cause:

Start of large-capacity motor.

Jumper or DC reactor is not connected across terminals P-P1.



Remedy:

Check the power supply system equipment such as power supply.

Connect a jumper or DC reactor across terminals P-P1.
E.FIN

Fin overheat

Cause:

Too high ambient temperature.

Heatsink clogging.



Remedy:

Set the ambient temperature to within the specifications.
E.GF

Output side earth (ground) fault overcurrent protection

Cause:

Earth (ground) fault in the motor and connection cable.



Remedy:

Remedy the earth (ground) fault portion.
E.OHT

External thermal relay operation

Cause:

Motor overheating.

Value of 7 (OH signal) is set incorrectly in any of Pr. 180 to Pr. 186.



Remedy:

Reduce the load and operating duty.
E.OLT

Stall prevention (Stll Prev STP)

Cause:

Motor used under overload conditions.



Remedy:

Reduce the load weight.
E.OPT

Option alarm

Cause:

Number of communication options fitted is more than one.

AC power supply connected to R, S, T terminals when high power factor converter is connected.



Remedy:

Reduce the communication options used to one.

Check the parameter (Pr. 30) setting and wiring.

Contact sales representative if inverter is damaged by AC power connection.
E.OP1 to E.OP3

Option slot alarm 1 to 3

Cause:

Wrong option function setting and operation.

Plug-in option not connected securely.

Communication cable wire breakage.

Termination resistor not fitted properly.



Remedy:

Confirm the option function setting, etc.

Connect the plug-in option securely.
E.PE

Parameter storage device alarm (Corrupt Memry)

Cause:

Too many parameter write times (E2PROM fault).



Remedy:

Change the inverter.
E.PUE

Parameter unit disconnection (PU Leave Out)

Cause:

Loose fitting of the DU or PU.

Incorrect Pr. 75 setting.



Remedy:

Fit the DU and PU securely.
E.RET

Retry count exceeded (Retry No Over)

Cause:

Operation could not be resumed within the set number of retries.



Remedy:

Eliminate the cause of the error preceding this error indication.
E.CPU

CPU error (CPU Fault)

Cause:

Arithmetic operation of built-in CPU did not end within predetermined period.



Remedy:

Make connection securely.
E. 3

Option fault (Fault 3)

Cause:

Communication option not plugged in securely.

Excess noises around the inverter.



Remedy:

Take measures against noises if there are devices producing excess noises.

Contact your sales representative.
E.6 / E.7

CPU error

Cause:

Check for excess electrical noises around the inverter.



Remedy:


  • Connect devices securely.

  • If there are any devices generating excess electrical noises around the inverter, take measures against noises.

  • Contact your sales representative.


E.P24

24VDC power output short circuit

Cause:

Check for a short circuit in the PC terminal output.



Remedy:

Remedy the short circuit portion.
E.CTE

Operation panel power supply short circuit

Cause:

Check for a short circuit in the PU connector cable.



Remedy:

Check the PU and cable.
E.LF

Output phase failure protection

Cause:


  • Check the wiring (Check the motor for a fault).

  • Check that the capacity of the used motor is not smaller than the inverter capacity.





Remedy:


  • Wire the cables properly.

  • Check the setting of Pr. 251 “output phase failure protection selection”.


FN

Fan fault

Cause:

Check the cooling fan for a fault.



Remedy:

Change the fan.
OL

Stall prevention (Over current)

Cause:

Check the motor for use under overload.



Remedy:

The acceleration/deceleration time may change. Increase the stall prevention operation level with Pr. 22 “stall prevention operation level” or disable stall prevention with Pr. 156 “stall prevention operation selection”.
oL

Stall prevention (overvoltage)

Cause:

Check for sudden speed reduction.



Remedy:

The deceleration time may change. Increase the deceleration time with Pr. 8 “deceleration time”.
PS

PU stop

Cause:

Check for a stop made by pressing the STOP/RESET key of the operation panel.



Remedy:

Refer to page 102 (release the PU stop mode).
TH

Electronic overcurrent protection prealarm

Cause:

Check for large load or sudden acceleration.



Remedy:

Reduce the load volume or the frequency of operation.
Err.

Error (Operation Error)

Cause:

This alarm appears if:

  • The RES signal is on.

  • You attempted to set any parameter value in the external operation mode.

  • You attempted to change the operation mode during operation.

  • You attempted to set any parameter value outside its setting range.

  • You attempted to set any parameter value during operation (while signal STF or STR is ON).

  • You attempted to make parameter setting when Pr. 77 “parameter write disable selection” has been set to disable parameter write.





Remedy:

Perform operation correctly.