5.1 Status monitoring function
5.1.1 Standard Monitoring Mode
Default display: Output frequency (f710=0), can be switched through f710 to display: output current (1), frequency command value (2), input voltage (3), output voltage (4), torque (7), etc.
Peak/minimum monitoring: f709=1 (peak hold), f709=2 (minimum hold), triggered by EASY key (f750=3) for measurement.
5.1.2 Status Monitoring Mode
Entry method: Press the MODE button twice, and the MON light will turn on.
Monitoring content: frequency command value, output current, output voltage, terminal input status, terminal output status, PID feedback value, overload rate, etc. Multiple monitoring items are supported and can be switched through dial-up settings.
5.1.3 Fault History Monitoring
Entry method: When the MON light flashes, enter to view the fault codes, frequency, current, voltage, and other data of the last 8 trips.
5.2 Common Fault Codes and Handling
5.2.1 Overcurrent faults (oc1, oc2, oc3)
Fault cause: ① Motor short circuit, grounding; ② Excessive load; ③ The acceleration time is too short; ④ Terminal wiring error; ⑤ Internal malfunction of the frequency converter.
Processing steps:
Power off and check the insulation of the motor winding, eliminate short circuits and grounding faults.
Check if the load is stuck, clean any foreign objects, and ensure that the load is within the rated range.
Increase the acceleration time (acc) or enable automatic acceleration (au1=1).
Recheck the wiring of the main circuit terminals to ensure there are no misconnections or looseness.
If all of the above are normal, contact a Toshiba dealer to inspect the internal of the frequency converter.
5.2.2 Overvoltage faults (op1, op2, op3)
Fault cause: ① High power supply voltage; ② The deceleration time is too short; ③ Excessive regeneration load; ④ Braking resistor not connected or faulty; ⑤ Overvoltage limit operation disabled.
Processing steps:
Measure the power supply voltage and confirm that it is within the rated range (+10%~-15%).
Increase deceleration time (dec) or enable overvoltage limit operation (f305=0).
Check if the brake resistor connection is correct and if the resistance value meets the requirements.
In scenarios with large regenerative loads (such as crane lowering), larger capacity braking resistors need to be replaced.
5.2.3 Overload fault (ol1, ol2, ol3)
Fault cause: ① The rated current of the motor does not match the THR; ② The load exceeds the rated value for a long time; ③ Error in setting electronic thermal protection characteristics; ④ Poor heat dissipation of the motor.
Processing steps:
Check the rated current of the motor and adjust the Thr parameter (e.g. if the rated current of the motor is 50% of the frequency converter, set Thr to 50%).
Check if the load is overloaded, reduce the load or replace the motor with a higher power.
Confirm that the aul parameters match the motor type (constant torque load set aul=1).
Check if the motor cooling fan is working properly and clean the dust on the cooling fins.
5.2.4 Overheating Fault (oh)
Fault cause: ① Excessive ambient temperature; ② Blockage of heat sink; ③ Cooling fan malfunction; ④ PWM carrier frequency is too high; ⑤ The frequency converter is running under overload.
Processing steps:
Improve ventilation environment and reduce ambient temperature (ensure ≤ 60 ° C).
Clean the dust and debris from the heat sink to ensure that the heat dissipation channel is unobstructed.
Check if the cooling fan is running, and replace the fan if there is a malfunction.
Reduce the PWM carrier frequency (f300, such as from 12kHz to 8kHz).
Check for long-term overload operation, adjust the load or increase the capacity of the frequency converter.
5.3 Fault reset method
Manual reset: After troubleshooting, press the STOP button on the panel twice or short-circuit the RES-CC terminal (Sink logic) for more than 1 second.
Automatic reset: Enable the retry function (f303=1-10), and the frequency converter will automatically retry starting after troubleshooting.
Attention: Before resetting, it is necessary to confirm that the cause of the fault has been eliminated and the operation command has been turned off to avoid accidents caused by sudden motor start-up.

6. Maintenance and upkeep standards
6.1 Maintenance Classification and Cycle
6.1.1 Daily Inspection (Daily)
Appearance inspection: There are no abnormal sounds or odors, and the shell is not overheated (can be touched by hand, no overheating phenomenon).
Running status: There are no fault codes on the display screen, and the indicator lights are in normal condition (such as RUN light, Charge light).
Environmental inspection: The ambient temperature and humidity are within the allowable range, and there is no accumulation of dust or oil mist.
6.1.2 Regular inspection (every 6 months)
Cleaning: Use compressed air (pressure ≤ 0.3MPa) to clean the dust on the heat sink and cooling fan. Do not clean with water or chemical solvents.
Wiring inspection: All terminal screws should be tightened to the specified torque, and the insulation layer of the wire should be checked for aging or damage.
Fan inspection: There is no abnormal noise when the cooling fan is running, and the air volume is normal. If the fan speed decreases or there is abnormal noise, it needs to be replaced.
Email:wang@kongjiangauto.com