VFD Reset method of protective function

Resetting the inverter
The inverter can be reset by performing any of the following operations. Note that the internal thermal integrated value of the electronic thermal relay function and the number of retries are cleared (erased) by resetting the inverter.
Recover about 1s after reset is cancelled.
Operation 1:  Using the operation panel, press to reset the inverter. (This may only be performed when a fault occurs)
Operation 2:  Switch power off once, then switch it on again.
Operation 3: Turn on the reset signal (RES) for more than 0.1s. (If the RES signal is kept on, "Err." appears (flickers) to indicate that the inverter is in a reset status.)

Motor will not start
1) Check the Pr. 0 Torque boost setting if V/F control is exercised.
2) Check the main circuit.
Check that a proper power supply voltage is applied. (Operation panel display is provided.)
Check that the motor is connected properly.
Check that the jumper across + and P1 is connected.
3) Check the input signals
Check that the start signal is input.
Check that both the forward and reverse rotation start signals are not input simultaneously.
Check that the frequency setting signal is not zero. (When the frequency command is 0Hz and the start command is entered, RUN LED of the operation panel flickers.)
Check that the AU analog signal is on when terminal 4 is used for frequency setting.
Check that the output stop signal (MRS) or reset signal (RES) is not on.
Check that the sink or source jumper connector is fitted securely.
Check that the jumper across S1-SC, S2-SC is connected.
4) Check the parameter settings
Check that Pr. 78 Reverse rotation prevention selection is not set.
Check that the Pr. 79 Operation mode selection setting is correct.
Check that the bias and gain (calibration parameter C2 to C7) settings are correct.
Check that the starting frequency Pr. 13 Starting frequency setting is not greater than the running frequency.
Check that frequency settings of each running frequency (such as multi-speed operation) are not zero. Check
that especially the maximum frequency Pr. 1 Maximum frequency is not zero.
Check that the Pr. 15 Jog frequency setting is not lower than the Pr. 13 Starting frequency value.
Check that the operation location by Pr. 551 is appropriate. (Example: write from the operation panel is disabled when parameter unit is connected)
5) Inspection of load
Check that the load is not too heavy.
Check that the shaft is not locked.
6) Others
Check that the operation panel display does not show a fault.

Motor generates abnormal noise
No carrier frequency noises (metallic noises) are generated.
Soft-PWM control to change the motor tone into an unoffending complex tone is factory-set to valid by Pr. 72 PWM frequency selection.
Adjust Pr. 72 PWM frequency selection to change the motor tone.
Check for any mechanical looseness.
Contact the motor manufacturer.
Check first when you have some troubles

Motor generates heat abnormally
Is the fan for the motor is running? (Check for dust accumulated.)
Check that the load is not too heavy. Lighten the load.
Are the inverter output voltages (U, V, W) balanced?
Check that the Pr. 0 Torque boost setting is correct.
Was the motor type set? Check the setting of Pr. 71 Applied motor.
When using any other manufacturer's motor, perform offline auto tuning.

Motor rotates in opposite direction
Check that the phase sequence of output terminals U, V and W is correct.
Check that the start signals (forward rotation, reverse rotation) are connected properly. (Refer to page 19)
Check that the Pr. 40 RUN key rotation direction selection setting is correct.

Speed greatly differs from the setting
Check that the frequency setting signal is correct. (Measure the input signal level.)
Check that the Pr. 1, Pr. 2, Pr. 19, Pr. 245, calibration parameter Pr. 125, Pr. 126, C2 to C7 settings are correct.
Check that the input signal lines are not affected by external noise. (use shielded cables)
Check that the load is not too heavy.
Check that the Pr. 31 to Pr. 36 (frequency jump) settings are correct.

Acceleration/deceleration is not smooth
Check that the acceleration and deceleration time settings are not too short.
Check that the load is not too heavy.
Check that the torque boost (Pr. 0, Pr. 46) setting is not too large to activate the stall function under V/F control.

Motor current is large
Check that the load is not too heavy.
Check that the Pr. 0 Torque boost setting is correct.
Check that the Pr. 3 Base frequency setting is correct.
Check that the Pr. 19 Base frequency voltage setting is correct
Check that the Pr. 14 Load pattern selection setting is correct.

Speed does not increase
Check that the Pr. 1 Maximum frequency setting is correct. (If you want to run the motor at 120Hz or more, set Pr. 18
High speed maximum frequency.
Check that the load is not too heavy. (In agitators, etc., load may become heavier in winter.)
Check that the torque boost (Pr. 0, Pr. 46) setting is not too large to activate the stall function under V/F control.
Check that the brake resistor is not connected to terminals + and P1 or P1-PR accidentally.

TROUBLESHOOTING
Check first when you have some troubles
Speed varies during operation
When slip compensation is set, the output frequency varies with load fluctuation between 0 and 2Hz. This is a normal
operation and is not a fault.
1) Inspection of load
Check that the load is not varying.
2) Check the input signals
Check that the frequency setting signal is not varying.
Check that the frequency setting signal is not affected by noise. Set filter to the analog input terminal using Pr. 74
Input filter time constant.
Check for a malfunction due to undesirable currents when the transistor output unit is connected.
3) Others
Check that the value of Pr. 80 Motor capacity is correct to the inverter capacity and motor capacity under generalpurpose
magnetic flux vector control.
Check that the wiring length is not exceeding 30m when general-purpose magnetic flux vector control is exercised. Perform offline auto tuning.
Check that the wiring length is not too long for V/F control.
Change the Pr. 19 Base frequency voltage setting (about 3%) under V/F control.

Operation mode is not changed properly
If the operation mode does not change correctly, check the following:
1) External input signal Check that the STF or STR signal is off. When it is on, the operation mode cannot be
changed.
2) Parameter setting
Check the Pr. 79 setting.
When the Pr. 79 Operation mode selection setting is "0" (initial value), the inverter is placed in the external
operation mode at input power-on. At this time, press on the operation panel (press when the
parameter unit (FR-PU04/FR-PU07) is used) to switch to the PU operation mode. For other values (1 to 4, 6, 7),
the operation mode is limited accordingly.
Check that the operation location by Pr. 551 is correct. (Example: write from the operation panel is disabled when
parameter unit is connected)

Operation panel display is not operating
Check that wiring is securely performed and installation is correct.
Make sure that the connector is fitted securely across terminals + and P1.

Parameter write cannot be performed
Make sure that operation is not being performed (signal STF or STR is not ON).
Make sure that you are not attempting to set the parameter in the external operation mode.
Check Pr. 77 Parameter write selection.
Check Pr. 161 Frequency setting/key lock operation selection.
Check that the operation location by Pr. 551 is correct. (Example: write from the operation panel is disabled when parameter unit is connected)

E--- Faults history
HOLD Operation panel lock
LOCd Password locked
Er1 to 4 Parameter write error
Err. Inverter reset
OL Stall prevention (overcurrent)
oL Stall prevention (overvoltage)
RB Regenerative brake prealarm
TH Electronic thermal relay function prealarm
PS PU stop
MT Maintenance signal output
UV Undervoltage
FN Fan fault
E.OC1 Overcurrent trip during acceleration
E.OC2 Overcurrent trip during constant speed
E.OC3 Overcurrent trip during deceleration or stop
E.OV1 Regenerative overvoltage trip during acceleration
E.OV2 Regenerative overvoltage trip during constant speed
E.OV3 Regenerative overvoltage trip during deceleration or stop
E.THT Inverter overload trip (electronic thermal relay function)
E.THM Motor overload trip(electronic thermal relay function)
E.FIN Fin overheat
E.ILF  Input phase loss
E.OLT Stall prevention
E. BE Brake transistor alarm detection
E.GF Output side earth (ground) fault overcurrent at start
E.LF Output phase loss
E.OHT External thermal relay operation
E.PTC PTC thermistor operation
E.PE Parameter storage device fault
E.PUE PU disconnection
E.RET Retry count excess
E.CPU CPU fault
E.CDO Output current detection value exceeded
E.IOH  Inrush current limit circuit fault
E.AIE  Analog input fault

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