Factory Automation

Inverters-FREQROL FR-A800 Series PROTECTIVE FUNCTION

Fault

When a protective function is activated, the inverter output is shut off and a Fault signal is output.

Overcurrent trip during acceleration

Operation panel
indication
E.OC1
FR-LU08 indication Overcurrent trip during acceleration
Name Overcurrent trip during acceleration
Description When the inverter output current reaches or exceeds approximately 235% of the rated current during acceleration, the protection circuit is activated and the inverter output is shut off.
Check point
  • Check for sudden speed acceleration.
  • Check if the downward acceleration time is too long in a lift application.
  • Check for output short-circuit.
  • Check that the Pr.3 Base frequency setting is not 60 Hz when the motor rated frequency is 50 Hz.
  • Check if the stall prevention operation level is set too high. Check if the fast-response current limit operation is disabled.
  • Check that the regenerative driving is not performed frequently. (Check if the output voltage becomes larger than the V/F reference voltage at regenerative driving and overcurrent occurs due to increase in the motor current.)
  • Check that the power supply for RS-485 terminal is not shorted (under Vector control).
  • Check that the encoder wiring and the specifications (encoder power supply, resolution, differential/complementary) are correct. Check also that the motor wiring (U, V, W) is correct (under Vector control).
  • Check that the rotation direction is not switched from forward to reverse rotation (or from reverse to forward)during torque control under Real sensorless vector control.
  • Check that the inverter capacity matches with the motor capacity. (PM sensorless vector control)
  • Check if a start command is given to the inverter while the motor is coasting. (PM sensorless vector control)
Corrective action
  • Set the acceleration time longer. (Shorten the downward acceleration time of the lift.)
  • If "E.OC1" always appears at start, disconnect the motor once and restart the inverter. If "E.OC1" still appears, contact your sales representative.
  • Check the wiring to make sure that output short circuit does not occur.
  • Set 50 Hz in Pr.3 Base frequency. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Lower the stall prevention operation level. Activate the fast-response current limit operation. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Set the base voltage (rated voltage of the motor, etc.) in Pr.19 Base frequency voltage. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Check RS-485 terminal connection (under Vector control).
  • Check the wiring and specifications of the encoder and the motor. Perform the setting according to the specifications of the encoder and the motor (under vector control). (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Prevent the motor from switching the rotation direction from forward to reverse (or from reverse to forward)during torque control under Real sensorless vector control.
  • Choose inverter and motor capacities that match. (PM sensorless vector control)
  • Input a start command after the motor stops. Alternatively, use the automatic restart after instantaneous power failure/flying start function. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED)) (PM sensorless vector control)

Overcurrent trip during constant speed

Operation panel
indication
E.OC2
FR-LU08 indication Overcurrent trip during constant speed
Name Overcurrent trip during constant speed
Description When the inverter output current reaches or exceeds approximately 235% of the rated current during constantspeed operation, the protection circuit is activated and the inverter output is shut off.
Check point
  • Check for sudden load change.
  • Check for a short-circuit in the output circuit.
  • Check if the stall prevention operation level is set too high. Check if the fast-response current limit operation is disabled.
  • Check that the power supply for RS-485 terminal is not shorted (under Vector control).
  • Check that the rotation direction is not switched from forward to reverse rotation (or from reverse to forward) during torque control under Real sensorless vector control.
  • Check that the inverter capacity matches with the motor capacity. (PM sensorless vector control)
  • Check if a start command is given to the inverter while the motor is coasting. (PM sensorless vector control)
Corrective action
  • Keep the load stable.
  • Check the wiring to make sure that output short circuit does not occur.
  • Lower the stall prevention operation level. Activate the fast-response current limit operation. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Check RS-485 terminal connection (under Vector control).
  • Prevent the motor from switching the rotation direction from forward to reverse (or from reverse to forward) during torque control under Real sensorless vector control.
  • Choose inverter and motor capacities that match. (PM sensorless vector control)
  • Input a start command after the motor stops. Alternatively, use the automatic restart after instantaneous power failure/flying start function. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED)) (PM sensorless vector control)

OC During Dec

Operation panel
indication
E.OC3
FR-LU08 indication OC During Dec
Name Overcurrent trip during deceleration or stop
Description When the inverter output current reaches or exceeds approximately 235% of the rated current during deceleration (other than acceleration or constant speed), the protection circuit is activated and the inverter output is shut off.
Check point
  • Check for sudden speed reduction.
  • Check for a short-circuit in the output circuit.
  • Check for too fast operation of the motor's mechanical brake.
  • Check if the stall prevention operation level is set too high. Check if the fast-response current limit operation is disabled.
  • Check that the power supply for RS-485 terminal is not shorted (under Vector control).
  • Check that the rotation direction is not switched from forward to reverse rotation (or from reverse to forward) during torque control under Real sensorless vector control.
  • Check that the inverter capacity matches with the motor capacity. (PM sensorless vector control)
  • Check if a start command is given to the inverter while the motor is coasting. (PM sensorless vector control)
Corrective action
  • Set the deceleration time longer.
  • Check the wiring to make sure that output short circuit does not occur.
  • Check the mechanical brake operation.
  • Lower the stall prevention operation level. Activate the fast-response current limit operation. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Check RS-485 terminal connection (under Vector control).
  • Prevent the motor from switching the rotation direction from forward to reverse (or from reverse to forward) during torque control under Real sensorless vector control.
  • Choose inverter and motor capacities that match. (PM sensorless vector control)
  • Input a start command after the motor stops. Alternatively, use the automatic restart after instantaneous power failure/flying start function. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED)) (PM sensorless vector control)

OV During Acc

Operation panel
indication
E.OV1
FR-LU08 indication OV During Acc
Name Regenerative overvoltage trip during acceleration
Description If regenerative power causes the inverter's internal main circuit DC voltage to reach or exceed the specified value, the protection circuit is activated to stop the inverter output. The circuit may also be activated by a surge voltage produced in the power supply system.
Check point
  • Check for too slow acceleration. (e.g. during downward acceleration in vertical lift load)
  • Check that the Pr.22 Stall prevention operation level is not set to the no load current or lower.
  • Check if the stall prevention operation is frequently activated in an application with a large load inertia.
Corrective action
  • Set the acceleration time shorter.
    Use the regeneration avoidance function (Pr.882 to Pr.886). (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Set a value larger than the no load current in Pr.22.
  • Set Pr.154 Voltage reduction selection during stall prevention operation = "10 or 11". (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))

Steady spd OV

Operation panel
indication
E.OV2
FR-LU08 indication Steady spd OV
Name Regenerative overvoltage trip during constant speed
Description If regenerative power causes the inverter's internal main circuit DC voltage to reach or exceed the specified value, the protection circuit is activated to stop the inverter output. The circuit may also be activated by a surge voltage produced in the power supply system.
Check point
  • Check for sudden load change.
  • Check that the Pr.22 Stall prevention operation level is not set to the no load current or lower.
  • Check if the stall prevention operation is frequently activated in an application with a large load inertia.
  • Check that acceleration/deceleration time is not too short.
Corrective action
  • Keep the load stable.
  • Use the regeneration avoidance function (Pr.882 to Pr.886). (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Use the brake unit or power regeneration common converter (FR-CV) as required.
  • Set a value larger than the no load current in Pr.22.
  • Set Pr.154 Voltage reduction selection during stall prevention operation = "10 or 11". (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Set the acceleration/deceleration time longer. (Under Vector control or Advanced magnetic flux vector control,the output torque can be increased. However, sudden acceleration may cause an overshoot in speed, resulting in an occurrence of overvoltage.)

OV During Acc

Operation panel
indication
E.OV3
FR-LU08 indication OV During Acc
Name Regenerative overvoltage trip during deceleration or stop
Description If regenerative power causes the inverter's internal main circuit DC voltage to reach or exceed the specified value, the protection circuit is activated to stop the inverter output. The circuit may also be activated by a surge voltage produced in the power supply system.
Check point
  • Check for sudden speed reduction.
  • Check if the stall prevention operation is frequently activated in an application with a large load inertia.
Corrective action
  • Set the deceleration time longer. (Set the deceleration time which matches the moment of inertia of the load.)
  • Make the brake cycle longer.
  • Use the regeneration avoidance function (Pr.882 to Pr.886). (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Use the brake unit or power regeneration common converter (FR-CV) as required.
  • Set Pr.154 Voltage reduction selection during stall prevention operation = "10 or 11". (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))

Inv. Overload

Operation panel
indication
E.THT
FR-LU08 indication Inv. Overload
Name Inverter overload trip (Electronic thermal O/L relay)
Description If the temperature of the output transistor elements exceeds the protection level with a rated output current or higher flowing without the overcurrent trip (E.OC[]), the inverter output is stopped. (Overload capacity 150% 60s)
Check point
  • Check that acceleration/deceleration time is not too short.
  • Check that torque boost setting is not too large (small).
  • Check that load pattern selection setting is appropriate for the load pattern of the using machine.
  • Check the motor for the use under overload.
  • Check that the encoder wiring and the specifications (encoder power supply, resolution, differential/complementary) are correct. Check also that the motor wiring (U, V, W) is correct (under Vector control).
Corrective action
  • Set the acceleration/deceleration time longer.
  • Adjust the torque boost setting.
  • Set the load pattern selection setting according to the load pattern of the using machine.
  • Reduce the load.
  • Check the wiring and specifications of the encoder and the motor. Perform the setting according to the specifications of the encoder and the motor (under vector control). (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))

Motor Ovrload

Operation panel
indication
E.THM
FR-LU08 indication Motor Ovrload
Name Motor overload trip (electronic thermal relay function)
Description The electronic thermal O/L relay function in the inverter detects motor overheat, which is caused by overload or reduced cooling capability during low-speed operation. When the cumulative heat value reaches 85% of the Pr.9 Electronic thermal O/L relay setting, pre-alarm (TH) is output. When the accumulated value reaches the specified value, the protection circuit is activated to stop the inverter output. When the inverter is used to drive a dedicated motor, such as a multiple-pole motor, or several motors, the motor cannot be protected by the electronic thermal O/L relay. Install an external thermal relay on the inverter output side.
Check point
  • Check the motor for the use under overload.
  • Check that the setting of Pr.71 Applied motor for motor selection is correct. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Check that the stall prevention operation setting is correct.
Corrective action
  • Reduce the load.
  • For a constant-torque motor, set the constant-torque motor in Pr.71.
  • Set the stall prevention operation level accordingly. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))

H/Sink O/Temp

Operation panel
indication
E.FIN
FR-LU08 indication H/Sink O/Temp
Name Heatsink overheat
Description When the heatsink overheats, the temperature sensor is activated, and the inverter output is stopped.
The FIN signal can be output when the temperature becomes approximately 85% of the heatsink overheat protection operation temperature.
For the terminal used for the FIN signal output, assign the function by setting "26 (positive logic) or 126 (negative logic)" from Pr.190 to Pr.196 (Output terminal function selection). (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
Check point
  • Check for too high surrounding air temperature.
  • Check for heatsink clogging.
  • Check that the cooling fan is not stopped. (Check that FN is not displayed on the operation panel.)
Corrective action
  • Set the surrounding air temperature to within the specifications.
  • Clean the heatsink.
  • Replace the cooling fan.

Instantaneous power failure

Operation panel
indication
E.IPF
FR-LU08 indication Instantaneous power failure
Name Instantaneous power failure (Standard models and IP55 compatible models only)
Description If a power failure occurs (or when power input to the inverter is shut off) for longer than 15 ms, the instantaneous power failure protective function is activated to shut off the inverter output in order to prevent the control circuit from malfunctioning. If a power failure persists for 100 ms or longer, the fault warning output is not provided, and the inverter restarts if the start signal is ON upon power restoration. (The inverter continues operating if an instantaneous power failure is within 15 ms.) In some operating status (load magnitude, acceleration/deceleration time setting, etc.), overcurrent or other protection may be activated upon power restoration.
When instantaneous power failure protection is activated, the IPF signal is output. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
Check point Find the cause of instantaneous power failure occurrence.
Corrective action
  • Remedy the instantaneous power failure.
  • Prepare a backup power supply for instantaneous power failure.
  • Set the function of automatic restart after instantaneous power failure (Pr.57). (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))

Under Voltage

Operation panel
indication
E.UVT
FR-LU08 indication Under Voltage
Name Undervoltage (Standard models and IP55 compatible models only)
Description If the power supply voltage of the inverter decreases, the control circuit will not perform normal functions. In addition, the motor torque will be insufficient and/or heat generation will increase. To prevent this, if the power supply voltage decreases to about 150 VAC (300 VAC for the 400 V class) or below, this function shuts off the inverter output.
When a jumper is not connected across P/+ and P1, the undervoltage protective function is activated.
When undervoltage protection is activated, the IPF signal is output. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
Check point
  • Check if a high-capacity motor is driven.
  • Check if the jumper is connected across terminals P/+ and P1.
Corrective action
  • Check the devices on the power supply line such as the power supply itself. If this function is activated due to unstable voltage in the power supply, change the undervoltage level (DC bus voltage value). (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Do not remove the jumper across terminals P/+ and P1 except when connecting a DC reactor.
  • If the problem still persists after taking the above measure, contact your sales representative.

Input phase loss

Operation panel
indication
E.ILF
FR-LU08 indication Input phase loss
Name Input phase loss (Standard models and IP55 compatible models only)
Description When Pr.872 Input phase loss protection selection is enabled ("1") and one of the three-phase power input is lost, the inverter output is shut off. This protective function is not available when Pr.872 is set to the initial value (Pr.872 = "0"). (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
Check point Check for a break in the cable for the three-phase power supply input.
Corrective action
  • Wire the cables properly.
  • Repair a break portion in the cable.

Stall Prev STP

Operation panel
indication
E.OLT
FR-LU08 indication Stall Prev STP
Name Stall prevention stop
Description [V/F] [Magnetic flux]
If the output frequency has fallen to 0.5 Hz by stall prevention operation and remains for 3 seconds, a fault (E.OLT) appears and the inverter is shut off. OL appears while stall prevention is being activated.
[Sensorless] [Vector] [PM]
When speed control is performed, a fault (E.OLT) appears and the inverter output is shut off if frequency drops to the Pr.865 Low speed detection (initial value is 1.5 Hz) setting by torque limit operation and the output torque exceeds the Pr.874 OLT level setting (initial value is 150%) setting and remains 3 seconds.
Check point
  • Check the motor for the use under overload.
  • Check that the Pr.865 and Pr.874 values are correct.
    (Check the Pr.22 Stall prevention operation level setting under V/F control and Advanced magnetic flux vector control.)
  • Check if a motor is connected under PM sensorless vector control.
Corrective action
  • Reduce the load.
  • Change the Pr.22, Pr.865, and Pr.874 values. (Check the Pr.22 setting under V/F control and Advanced magnetic flux vector control.)
  • For the test operation without connecting a motor, select the PM sensorless vector control test operation. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Also check that the stall prevention (overcurrent) warning (OL) or the stall prevention (overvoltage) warning (oL) countermeasure is taken.

Motor Step Out

Operation panel
indication
E.SOT
[PM]
FR-LU08 indication Motor Step Out
Name Loss of synchronism detection
Description The inverter output is shut off when the motor operation is not synchronized. (This function is only available under PM sensorless vector control.)
Check point
  • Check that the PM motor is not driven overloaded.
  • Check if a start command is given to the inverter while the PM motor is coasting.
  • Check if a motor is connected under PM sensorless vector control.
  • Check if a PM motor other than the MM-CF series is driven.
Corrective action
  • Set the acceleration time longer.
  • Reduce the load.
  • If the inverter restarts during coasting, set Pr.57 Restart coasting time ≠ "9999", and select the automatic restart after instantaneous power failure.
  • Check the connection of the IPM motor.
  • For the test operation without connecting a motor, select the PM sensorless vector control test operation.
    (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED) )
  • Drive an IPM motor (MM-CF series).
  • When driving an IPM motor other than MM-CF series, offline auto tuning must be performed. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))

Upper limit fault detection

Operation panel
indication
E.LUP
FR-LU08 indication Upper limit fault detection
Name Upper limit fault detection
Description The inverter output is shut off when the load exceeds the upper limit fault detection range. This protective function is not available in the initial setting of Pr.1490 (Pr.1490 = "9999").
Check point
  • Check if too much load is applied to the equipment.
  • Check that the load characteristics settings are correct.
Corrective action
  • Inspect the equipment.
  • Set the load characteristics (Pr.1481 to Pr.1487) correctly.

Lower limit fault detection

Operation panel
indication
E.LDN
FR-LU08 indication Lower limit fault detection
Name Lower limit fault detection
Description The inverter output is shut off when the load falls below the lower limit fault detection range. This protective function is not available in the initial setting of Pr.1491 (Pr.1491 = "9999").
Check point
  • Check if the equipment load is too light.
  • Check that the load characteristics settings are correct.
Corrective action
  • Inspect the equipment.
  • Set the load characteristics (Pr.1481 to Pr.1487) correctly.

Br. Cct. Fault

Operation panel
indication
E.BE
FR-LU08 indication Br. Cct. Fault
Name Brake transistor alarm detection
Description
  • The inverter output is shut off if a fault due to damage of the brake transistor and such occurs in the brake circuit.
    In such a case, the power supply to the inverter must be shut off immediately.
  • Appears when an internal circuit fault occurred for separated converter types and IP55 compatible models.
Check point
  • Reduce the load inertia.
  • Check that the brake duty is proper.
Corrective action Replace the inverter.

Ground Fault

Operation panel
indication
E.GF
FR-LU08 indication Ground Fault
Name Output side earth (ground) fault overcurrent
Description The inverter output is shut off if an earth (ground) fault overcurrent flows due to an earth (ground) fault that occurred on the inverter's output side (load side).
Check point Check for a ground fault in the motor and connection cable.
Corrective action Remedy the earth (ground) fault portion.

Output phase loss

Operation panel
indication
E.LF
FR-LU08 indication Output phase loss
Name Output phase loss
Description The inverter output is shut off if one of the three phases (U, V, W) on the inverter's output side (load side) is lost.
Check point
  • Check the wiring. (Check that the motor is normally operating.)
  • Check that the capacity of the motor used is not smaller than that of the inverter.
  • Check if a start command is given to the inverter while the motor is coasting. (PM sensorless vector control)
Corrective action
  • Wire the cables properly.
  • Input a start command after the motor stops. Alternatively, use the automatic restart after instantaneous power failure/flying start function (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED)). (PM sensorless vector control)

Ext TH relay oper

Operation panel
indication
E.OHT
FR-LU08 indication Ext TH relay oper
Name External thermal relay operation
Description The inverter output is shut off if the external thermal relay provided for motor overheat protection or the internally mounted thermal relay in the motor, etc. switches ON (contacts open). This function is available when "7" (OH signal) is set in any of Pr.178 to Pr.189 (Input terminal function selection). This protective function is not available in the initial status. (OH signal is not assigned.)
Check point
  • Check for motor overheating.
  • Check that the value "7" (OH signal) is set correctly to any of Pr.178 to Pr.189 (Input terminal function selection).
Corrective action
  • Reduce the load and operation duty.
  • Even if the relay contacts are reset automatically, the inverter will not restart unless it is reset.

PTC thermistor oper

Operation panel
indication
E.PTC
FR-LU08 indication PTC thermistor oper
Name PTC thermistor operation
Description The inverter output is shut off if resistance of the PTC thermistor connected between terminal 2 and terminal 10 is equal to or higher than the Pr.561 PTC thermistor protection level setting for a continuous time equal to or longer than the setting value in Pr.1016 PTC thermistor protection detection time. When the initial value (Pr.561 = "9999") is set, this protective function is not available.
Check point
  • Check the connection with the PTC thermistor.
  • Check the Pr.561 and Pr.1016 settings.
  • Check the motor for operation under overload.
Corrective action Reduce the load.

Option Fault

Operation panel
indication
E.OPT
FR-LU08 indication Option Fault
Name Option Fault
Description
  • Appears when the AC power supply is connected to terminal R/L1, S/L2, or T/L3 accidentally when a high power factor converter (FR-HC2) or power regeneration common converter (FR-CV) is connected (when Pr.30 Regenerative function selection = "2").
  • Appears when torque command by the plug-in option is selected using Pr.804 Torque command source selection and no plug-in option is mounted. This function is available under torque control.
  • Appears when either one of a Vector control compatible plug-in option or a control terminal option (FR-A8TP) is not installed during machine end orientation control.
  • Appears when the switch for manufacturer setting of the plug-in option is changed.
  • Appears when a communication option is connected while Pr.296 Password lock level = "0 or 100".
Check point
  • Check that the AC power supply is not connected to terminal R/L1, S/L2, or T/L3 when a high power factor converter (FR-HC2) or power regeneration common converter (FR-CV) is connected (when Pr.30 = "2").
  • Check that the plug-in option for torque command setting is connected.
  • Check that the Vector control plug-in option and the control terminal option (FR-A8TP) are installed correctly.
    Check that the Pr.393 Orientation selection and Pr.862 Encoder option selection settings are correct.
  • Check for the password lock with a setting of Pr.296 = "0, 100".
Corrective action
  • Check the Pr.30 setting and wiring.
  • The inverter may be damaged if the AC power supply is connected to terminal R/L1, S/L2, or T/L3 when a high power factor converter is connected. Contact your sales representative.
  • Check for connection of the plug-in option. Check the Pr.804 setting.
  • Install the Vector control plug-in option and the control terminal option (FR-A8TP) correctly. Set Pr.393 and Pr.862 correctly. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Set the switch on the plug-in option, which is for manufacturer setting, back to the initial setting. (Refer to the Instruction Manual of each option.)
  • To apply the password lock when installing a communication option, set Pr.296 ≠ "0, 100". (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))

Option1 Fault to Option3 Fault

Operation panel
indication
E.OP1 to E.OP3
FR-LU08 indication Option1 Fault to Option3 Fault
Name Communication option fault
Description
  • The inverter output is shut off if a communication line error occurs in the communication option.
  • This function stops the inverter output when a communication line error occurs on the CC-Link IE Field network communication circuit board of the FR-A800-GF.
  • When the FR-A8APR is installed to the inverter and a motor with a resolver is used, the inverter output is shut off if the FR-A8APR fails or the wiring of the resolver is not properly connected.
Check point
  • Check for an incorrect option function setting and operation.
  • Check that the plug-in option is plugged into the connector securely.
  • For the FR-A800-GF, check that the CC-Link IE Field Network communication circuit board is securely installed to the connector of the inverter control circuit board.
  • Check for a break in the communication cable.
  • Check that the terminating resistor is fitted properly.
  • Check that the wiring of the resolver is correct. (When the FR-A8APR is used.)
Corrective action
  • Check the option function setting, etc.
  • Connect the plug-in option securely.
  • Connect the CC-Link IE Field Network communication circuit board of the FR-A800-GF securely.
  • Check the connection of communication cable.
  • Check the wiring of the resolver (when the FR-A8APR is used).
  • If the fault occurs again when the inverter is reset, contact your sales representative.

Fault 16 to Fault 20

Operation panel
indication
E.16 to E.20
FR-LU08 indication Fault 16 to Fault 20
Name User definition error by the PLC function
Description The protective function is activated by setting "16 to 20" in the special register SD1214 for the PLC function. The inverter output is shut off when the protective function is activated.
The protective function is activated when the PLC function is enabled. This protective function is not available in the initial setting (Pr.414 = "0").
Any character string can be displayed on FR-LU08 or FR-PU07 by sequence programs.
Check point Check if "16 to 20" is set in the special register SD1214.
Corrective action Set a value other than "16 to 20" in the special register SD1214.

Internal storage device fault

Operation panel
indication
E.PE6
FR-LU08 indication Fault
Name Internal storage device fault
Description This protective function is activated by an inverter reset if writing data fails due to power-OFF or a data fault occurs in the storage device during parameter operations.
Check point Check if the power was turned OFF during parameter operations.
Corrective action Check the power supply or the devices on the power system to check that the devices have no fault.
  • When E.PE6 occurs due to power-OFF during parameter operations:
    Check the read value of Pr.890. When the value is "7" or smaller, perform All parameter clear and then an inverter reset. The parameters that had been changed before All parameter clear must be set again.
  • When E.PE6 occurs due to other reason (such as turning OFF/ON the power or an inverter reset):
    Contact your sales representative.

Corrupt Memory

Operation panel
indication
E.PE
FR-LU08 indication Corrupt Memory
Name Parameter storage device fault
Description The inverter output is shut off if a fault occurs in the parameter stored. (EEPROM failure)
Check point Check for too many number of parameter write times.
Corrective action Contact your sales representative.
Set "1" in Pr.342 Communication EEPROM write selection (write to RAM) for the operation which requires frequent parameter writing via communication, etc. Note that writing to RAM goes back to the initial status at power OFF.

PU disconnection

Operation panel
indication
E.PUE
FR-LU08 indication PU disconnection
Name PU disconnection
Description
  • The inverter output is shut off if communication between the inverter and PU is suspended, e.g. the operation panel or parameter unit is disconnected, when the disconnected PU disconnection function is valid in Pr.75 Reset selection/disconnected PU detection/PU stop selection.
  • The inverter output is shut off if communication errors occurred consecutively for more than permissible number of retries when Pr.121 PU communication retry count ≠ "9999" during the RS-485 communication.
  • The inverter output is shut off if communication is broken within the period of time set in Pr.122 PU communication check time interval during the RS-485 communication via the PU connector.
Check point
  • Check that the operation panel or the parameter unit is connected properly.
  • Check the Pr.75 setting.
Corrective action Fit the operation panel or the parameter unit securely.

Retry count excess

Operation panel
indication
E.RET
FR-LU08 indication Retry count excess
Name Retry count excess
Description The inverter output is shut off if the operation cannot be resumed properly within the number of retries set in Pr.67 Number of retries at fault occurrence. This function is available when Pr.67 is set. This protective function is not available in the initial setting (Pr.67 = "0").
Check point Find the cause of the fault occurrence.
Corrective action Eliminate the cause of the fault preceding this fault indication.

PR storage alarm

Operation panel
indication
E.PE2
FR-LU08 indication PR storage alarm
Name Parameter storage device fault
Description The inverter output is shut off if a fault occurs in the parameter stored. (EEPROM failure)
Check point
Corrective action Contact your sales representative.

CPU fault/Error5/Error6/Error7

Operation panel
indication
E.CPU E. 5 E. 6 E. 7
FR-LU08 indication CPU fault Error5 Error6 Error7
Name CPU fault
Description The inverter output is shut off if the communication fault of the built-in CPU occurs.
Check point Check for devices producing excess electrical noises around the inverter.
Corrective action
  • Take measures against noises if there are devices producing excess electrical noises around the inverter.
  • Contact your sales representative.

Circuit fault

Operation panel
indication
E.CTE
FR-LU08 indication Circuit fault
Name Operation panel power supply short circuit/RS-485 terminals power supply short circuit
Description
  • When the power supply for the operation panel (PU connector) is shorted, the power output is shutoff and the inverter output is shut off. The use of the operation panel (parameter unit) and the RS-485 communication via the PU connector are disabled.
    To reset, enter the RES signal from the terminal, reset through communication via the RS-485 terminals, or switch power OFF then ON again.
  • When the power supply for the RS-485 terminals are short circuited, this function shuts off the power output. At this time, communication from the RS-485 terminals cannot be made.
    To reset, use [STOP/RESET]key on the operation panel, enter the RES signal, or switch power OFF then ON again.
Check point
  • Check that the PU connector cable is not shorted.
  • Check that the RS-485 terminals are connected correctly.
Corrective action
  • Check PU and the cable.
  • Check the connection of the RS-485 terminals.

24 VDC power fault

Operation panel
indication
E.P24
FR-LU08 indication 24 VDC power fault
Name 24 VDC power fault
Description
  • When the 24 VDC power output from the PC terminal is shorted, this function shuts off the power output.
    At this time, all external contact inputs switch OFF. The inverter cannot be reset by entering the RES signal.
    To reset it, use the operation panel, or switch power OFF, then ON again.
Check point
  • Check for a short circuit in the PC terminal output.
  • Check that the 24 V external power supply voltage is correct.
Corrective action
  • Repair the short-circuited portion.
  • Supply the power at 24 V. (If the power with insufficient voltage is supplied to the 24 V input circuit for a long time, the inverter internal circuit may heats up. Although it will not damage the inverter, supply power at the correct voltage.)

OC detect level

Operation panel
indication
E.CDO
FR-LU08 indication OC detect level
Name Abnormal output current detection
Description The inverter output is shut off if the output current exceeds the Pr.150 Output current detection level setting. This functions is available when "1" is set in Pr.167 Output current detection operation selection. When the initial value (Pr.167 = "0") is set, this protective function is not available.
Check point Check the settings of Pr.150, Pr.151 Output current detection signal delay time, Pr.166 Output current detection signal retention time, and Pr.167. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED).)

Inrush overheat

Operation panel
indication
E.IOH
FR-LU08 indication Inrush overheat
Name Inrush current limit circuit fault (Standard models and IP55 compatible models only)
Description The inverter output is shut off when the resistor of the inrush current limit circuit is overheated. The inrush current limit circuit is faulty.
Check point
  • Check that frequent power ON/OFF is not repeated.
  • Check if the input side fuse (5A) in the power supply circuit of the inrush current limit circuit contactor (FR-A840-03250(110K) or higher) is blown.
  • Check that the power supply circuit of inrush current limit circuit contactor is not damaged.
Corrective action Configure a circuit where frequent power ON/OFF is not repeated.
If the problem still persists after taking the above measure, contact your sales representative.

VFD Comm error

Operation panel
indication
E.SER
FR-LU08 indication VFD Comm error
Name Communication fault (inverter)
Description The inverter output is shut off when communication error occurs consecutively for the permissible number of retries or more when Pr.335 RS-485 communication retry count ≠ "9999" during RS-485 communication through the RS-485 terminals. The inverter output is also shut off if communication is broken for the period of time set in Pr.336 RS-485 communication check time interval.
Check point Check the RS-485 terminal wiring.
Corrective action Perform wiring of the RS-485 terminals properly.

Analog input fault

Operation panel
indication
E.AIE
FR-LU08 indication Analog input fault
Name Analog input fault
Description The inverter output is shut off when a 30 mA or higher current or a 7.5 V or higher voltage is input to terminal 2 while the current input is selected by Pr.73 Analog input selection, or to terminal 4 while the current input is selected by Pr.267 Terminal 4 input selection.
Check point Check the Pr.73, Pr.267, and the voltage/current input switch settings. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
Corrective action Either give a current less than 30 mA, or set Pr.73, Pr.267, and the voltage/current input switch to the voltage input and input a voltage.

USB comm error

Operation panel
indication
E.USB
FR-LU08 indication USB comm error
Name USB communication fault
Description The inverter output is shut off when the communication is cut off for the time set in Pr.548 USB communication check time interval.
Check point Check that the USB communication cable is connected securely.
Corrective action
  • Check the Pr.548 setting.
  • Connect the USB communication cable securely.
  • Increase the Pr.548 setting or set "9999." (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))

safety circuit fault

Operation panel
indication
E.SAF
FR-LU08 indication safety circuit fault
Name Safety circuit fault
Description
  • The inverter output is shut off when a safety circuit fault occurs.
  • The inverter output is shut off if the either of the wire between S1 and SIC or S2 and SIC becomes nonconductive while using the safety stop function.
  • When the safety stop function is not used, the inverter output is shut off when the shorting wire between terminals S1 and PC or across S2 and PC is disconnected.
Check point
  • Check that the safety relay module or the connection has no fault when using the safety stop function.
  • Check if the shorting wire between S1 and PC or between S2 and PC is disconnected when not using the safety stop function.
Corrective action
  • When using the safety stop function, check that wiring of terminal S1, S2 and SIC is correct and the safety stop input signal source such as a safety relay module is operating properly. Refer to the Safety Stop Function Instruction Manual for causes and countermeasures. (Contact your sales representative for the manual.)
  • When the safety stop function is not used, short across terminals S1 and PC and across S2 and PC with shorting wires. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED)

PBT fault/Internal circuit fault

Operation panel
indication
E.PBT E.13
FR-LU08 indication PBT fault Internal circuit fault
Name Internal circuit fault
Description The inverter output is shut off when an internal circuit fault occurs.
Corrective action Contact your sales representative.

Overspeed occurrence

Operation panel
indication
E.OS
FR-LU08 indication Overspeed occurrence
Name Overspeed occurrence
Description The inverter output is shut off when the motor speed exceeds the Pr.374 Overspeed detection level under encoder feedback control, Real sensorless vector control, Vector control, and PM sensorless vector control. This protective function is not available in the initial status.
Check point
  • Check that the Pr.374 setting is correct.
  • Check that the number of encoder pulses does not differ from the actual number of Pr.369 (Pr.851) Number of encoder pulses. (Under encoder feedback control or vector control)
Corrective action
  • Set the Pr.374 correctly.
  • Set Pr.369 (Pr.851) correctly. (Under encoder feedback control or vector control)

Spd deviation fault

Operation panel
indication
E.OSD
[Vector]
FR-LU08 indication Spd deviation fault
Name Speed deviation excess detection
Description
  • The inverter output is shut off if the motor speed is increased or decreased under the influence of the load etc. during Vector control with Pr.285 Overspeed detection frequency set and cannot be controlled in accordance with the speed command value.
  • If the motor is accelerated against the stop command accidentally, the deceleration check function (Pr.690) is activated to stop the inverter output.
Check point
  • Check that the settings of Pr.285 and Pr.853 Speed deviation time are correct.
  • Check for sudden load change.
  • Check that the setting of Pr.369 (Pr.851) Number of encoder pulses does not differ from the actual number of encoder pulses.
Corrective action
  • Set Pr.285 and Pr.853 correctly.
  • Keep the load stable.
  • Set Pr.369 (Pr.851) correctly.

Encoder signal loss

Operation panel
indication
E.ECT
FR-LU08 indication Encoder signal loss
Name Signal loss detection
Description The inverter output is shut off when the encoder signal is shut off under orientation control, encoder feedback control or vector control. This protective function is not available in the initial status.
Check point
  • Check for the encoder signal loss.
  • Check that the encoder specifications are correct.
  • Check for a loose connector.
  • Check that the switch setting of a Vector control compatible option is correct.
  • Check that the power is supplied to the encoder. Alternatively, check that the power is not supplied to the encoder later than the inverter.
  • Check that the voltage of the power supplied to the encoder is the same as the encoder output voltage.
Corrective action
  • Remedy the signal loss.
  • Use an encoder that meets the specifications.
  • Make connection securely.
  • Make a switch setting of a Vector control compatible option correctly. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Supply the power to the encoder. Or supply the power to the encoder at the same time when the power is supplied to the inverter.
    If the power is supplied to the encoder after sent to the inverter, check that the encoder signal is properly sent and set "0 (initial value)" in Pr.376 Encoder signal loss detection enable/disable selection to disable signal loss detection.
  • Make the voltage of the power supplied to the encoder the same as the encoder output voltage.

Position fault

Operation panel
indication
E.OD
[Vector]
FR-LU08 indication Position fault
Name Excessive position fault
Description The inverter output is shut off when the difference between the position command and position feedback exceeds the setting of Pr.427 Excessive level error during position control. This protective function is not available in the initial status.
Check point
  • Check that the position detecting encoder mounting orientation matches the parameter.
  • Check that the load is not large.
  • Check that the settings of Pr.427 and Pr.369 (Pr.851) Number of encoder pulses are correct.
Corrective action
  • Check the parameters.
  • Reduce the load.
  • Set Pr.427 and Pr.369 (Pr.851) correctly.

Orientation encoder no-signal

Operation panel
indication
E.ECA
FR-LU08 indication ENC direction fault
Name Orientation encoder no-signal
Description The inverter output is shut off when the encoder signal is shut off under orientation control. This protective function is not available in the initial status.
Check point
  • Check for the encoder signal loss.
  • Check that the encoder specifications are correct.
  • Check for a loose connector.
  • Check that the switch setting of a Vector control compatible option is correct.
  • Check that the power is supplied to the encoder. Alternatively, check that the power is not supplied to the encoder later than the inverter.
  • Check that the voltage of the power supplied to the encoder is the same as the encoder output voltage.
Corrective action
  • Remedy the signal loss.
  • Use an encoder that meets the specifications.
  • Make connection securely.
  • Make a switch setting of a Vector control compatible option correctly. (Refer to FR-A800 INSTRUCTION MANUAL(DETAILED))
  • Supply the power to the encoder. Or supply the power to the encoder at the same time when the power is supplied to the inverter.
    "If the power is supplied to the encoder after sent to the inverter, check that the encoder signal is properly sent and set ""0 (initial value)"" in Pr.376 Encoder signal loss detection enable/disable selection or Pr.855 Control terminal option-Signal loss detection enable/disable selection to disable signal loss detection."
  • Make the voltage of the power supplied to the encoder the same as the encoder output voltage.

E.MB1 Fault to E.MB7 Fault

Operation panel
indication
E.MB1 to 7
FR-LU08 indication E.MB1 Fault to E.MB7 Fault
Name Brake sequence fault
Description The inverter output is shut off when a sequence error occurs during use of the brake sequence function (Pr.278 to Pr.285). This protective function is not available in the initial status. (The brake sequence function is invalid.)(For the details of fault record, Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
Check point Find the cause of the fault occurrence.
Corrective action Check the set parameters and perform wiring properly.

Encoder phase fault

Operation panel
indication
E.EP
[Vector]
FR-LU08 indication Encoder phase fault
Name Encoder phase fault
Description The inverter output is shut off when the rotation command of the inverter differs from the actual motor rotation direction detected from the encoder during offline auto tuning. This protective function is not available in the initial status.
Check point
  • Check for mis-wiring of the encoder cable.
  • Check if the Pr.359 (Pr.852) Encoder rotation direction setting is incorrect.
Corrective action
  • Perform connection and wiring securely.
  • Change the Pr.359 (Pr.852) setting.

MagnetPole Pos Fault

Operation panel
indication
E.MP
[Vector]
FR-LU08 indication MagnetPole Pos Fault
Name Magnetic pole position unknown
Description When the offset value between the PM motor home magnetic pole position and the home position of the encoder (position detector) is unknown, the protective circuit is activated to stop the inverter output.
Check point
  • Check that the encoder position tuning was performed.
  • Check that the encoder position tuning ended properly. When Pr.1105 Encoder magnetic pole position offset = "9999", the encoder position tuning does not end properly.
Corrective action
  • Perform encoder position tuning with Pr.373 Encoder position tuning setting/status. (Refer to the Instruction Manual of the encoder option.)
  • Remove the cause of the tuning error, and perform tuning again. (Refer to the Instruction Manual of the encoder option.)

Fault

Operation panel
indication
E.EF
FR-LU08 indication Fault
Name External fault during output operation
Description When the X32 signal turns OFF (the contact opens) due to an external fault or other factor, the inverter output is shut off. This function is available when "32" is set in any of Pr.178 to Pr.189 (Input terminal function selection). This protective function is not available in the initial status (X32 signal is not assigned).
Check point Check that the X32 signal is OFF.
Corrective action Make sure that there is no problem in starting operation, and turn ON the X32 signal.

Abnormal Intnl Temp

Operation panel
indication
E.IAH
FR-LU08 indication Abnormal Intnl Temp
Name Abnormal internal temperature (Standard models and IP55 compatible models only)
Description The inverter output is shut off when the inverter internal temperature reaches the specified value or higher.
Check point
  • Check for too high surrounding air temperature.
  • Check if the internal air circulation fan or the cooling fan stops due to a fault.
Corrective action
  • Install an inverter suitable for the installation environment. (Refer to the Instruction Manual (Hardware).)
  • Replace the internal air circulation fan or the cooling fan.

4 mA input fault

Operation panel
indication
E.LCI
FR-LU08 indication 4 mA input fault
Name 4 mA input fault
Description The inverter output is shut off when the analog input current is 2 mA or less for the time set in Pr.778 4 mA input check filter. This function is available when Pr.573 4 mA input check selection = "2 or 3". (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED)) This protective function is not available in the initial status.
Check point
  • Check for a break in the wiring for the analog current input.
  • Check that the Pr.778 setting is not too short.
Corrective action
  • Check the wiring for the analog current input.
  • Set the Pr.778 setting larger.

Pre-charge fault

Operation panel
indication
E.PCH
FR-LU08 indication Pre-charge fault
Name Pre-charge fault
Description The inverter output is shut off when the pre-charge time exceeds Pr.764 Pre-charge time limit. The inverter output is shut off when the measured value exceeds Pr.763 Pre-charge upper detection level during precharging. This function is available when Pr.764 and Pr.763 are set (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED)). This protective function is not available in the initial status.
Check point
  • Check that the Pr.764 setting is not too short.
  • Check that the Pr.763 setting is not too small.
  • Check that the Pr.127 PID control automatic switchover frequency setting is not too low.
  • Check for a break in the connection to the pump.
Corrective action
  • Set the Pr.764 setting longer.
  • Set the Pr.763 setting larger.
  • Set the Pr.127 setting higher.
  • Check the connection to the pump.

PID signal fault

Operation panel
indication
E.PID
FR-LU08 indication PID signal fault
Name PID signal fault
Description The inverter output is shut off if the measured value exceeds the PID upper limit or PID lower limit parameter setting, or the absolute deviation value exceeds the PID deviation parameter setting during PID control. Set this function in Pr.131 PID upper limit, Pr.132 PID lower limit, Pr.553 PID deviation limit, and Pr.554 PID signal operation selection. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED)) This protective function is not available in the initial status.
Check point
  • Check the meter for a failure or break.
  • Check that the parameter settings are correct.
Corrective action
  • Check that the meter has no failure or break.
  • Set the parameters correctly.

Fault 1 to Fault 3

Operation panel
indication
E.1 to E.3
FR-LU08 indication Fault 1 to Fault 3
Name Option fault
Description
  • The inverter output is shut off when a contact fault is found between the inverter and the plug-in option, or when the communication option is not connected to the connector 1.
  • For the FR-A800-GF, the inverter output is shut off when a connector contact fault or the like occurs between the CC-Link IE Field network communication circuit board and the inverter control circuit board.
  • Appears when the switch for manufacturer setting of the plug-in option is changed.
Check point
  • Check that the plug-in option is plugged into the connector securely. (1 to 3 indicate connector numbers for connection of options.)
  • For the FR-A800-GF, check that the CC-Link IE Field Network communication circuit board is securely installed to the connector of the inverter control circuit board.
  • Check for excessive noise around the inverter.
  • Check if the communication option is connected to the connector 2 or 3.
Corrective action
  • Connect the plug-in option securely.
  • Connect the CC-Link IE Field Network communication circuit board of the FR-A800-GF securely.
  • Take measures against noises if there are devices producing excessive electrical noises around the inverter.
    If the problem still persists after taking the above measure, contact your sales representative.
  • Connect the communication option to the connector 1.
  • Set the switch on the plug-in option, which is for manufacturer setting, back to the initial setting. (Refer to the Instruction Manual of each option.)

Opst rot dtct fault

Operation panel
indication
E.11
[Sensorless]
FR-LU08 indication Opst rot dtct fault
Name Opposite rotation deceleration fault
Description The speed may not decelerate during low speed operation if the rotation direction of the speed command and the estimated speed differ when the rotation is changing from forward to reverse or from reverse to forward during torque control under Real sensorless vector control. The inverter output is shut off when overload occurs due to the un-switched rotation direction. This protective function is not available in the initial status (V/F control).
(This function is only available under Real sensorless vector control.)
Check point Check that the rotation direction is not switched from forward to reverse rotation (or from reverse to forward) during torque control under Real sensorless vector control.
Corrective action
  • Prevent the motor from switching the rotation direction from forward to reverse (or from reverse to forward) during torque control under Real sensorless vector control.
  • Contact your sales representative.

Fault

Operation panel
indication
E.EHR
FR-LU08 indication Fault
Name Ethernet communication fault (Data code: 231 (HE7))
Description
  • Appears when Ethernet communication is interrupted by physical factors while Pr.1431 Ethernet signal loss detection function selection = "3".
  • The inverter trips when Ethernet communication is cut off for the time set in Pr.1432 Ethernet communication check time interval or longer between the inverter and all devices with the IP addresses in the range specified for the Ethernet command source selection (Pr.1449 to Pr.1454).
  • Stops the inverter output when excessive noise occurs around the inverter.
  • When the CC-Link IE Field Network Basic is used, the inverter output is shut off when the data addressed to the own station is not received for the predetermined timeout period or longer, or when the status bit of the cyclic transmission addressed to the own station turns OFF (when the master controller gives a command to stop the cyclic transmission). (For the details of the timeout period, status bit of the cyclic transmission, and command to stop the cyclic transmission, refer to the Instruction Manual of the master controller which supports the CC-Link IE Field Network Basic.)
  • If an IP address of any other inverter falls within the IP address range set for command source selection while BACnet/IP is used, the inverter output will be shut off after the time period set in Pr.1432 after power is supplied to the inverter.
Check point
  • Check that the Ethernet board is installed onto the connector securely.
  • Check for a break in the Ethernet cable.
  • Check that the Pr.1432 setting is not too short.
  • Check for excessive noise around the inverter.
  • When the CC-Link IE Field Network Basic is used, check that the timeout period set in the master is not shorter than the period during which the inverter does not receive the data addressed to the own station.
  • When the CC-Link IE Field Network Basic is used, check that the status bit of the cyclic transmission addressed to the own station is not OFF.
  • When BACnet/IP is used, check that IP addresses of other inverters are not included in the Ethernet IP address range set for command source selection.
Corrective action
  • Connect the Ethernet board securely.
  • Check that the Ethernet cable is correctly connected to the Ethernet connector. Check that the Ethernet cable is not broken.
  • Set a larger value in Pr.1432.
  • When excessive noise occurs around the inverter, change the communication setting of the master. (Thenoise may be reduced by setting a shorter timeout period or increasing the number of retries in the communication setting of the master.)
  • When the CC-Link IE Field Network Basic is used, set a timeout period longer than the period during which the inverter does not receive the data addressed to the own station.
  • When the CC-Link IE Field Network Basic is used, turn ON the status bit of the cyclic transmission addressed to the own station.
  • When BACnet/IP is used, do not include IP addresses of other inverters in the Ethernet IP address range set for command source selection.

Warning

Output is not shut off when a protective function is activated.

OL

Operation panel
indication
OL
FR-LU08 indication OL
Name Stall prevention (overcurrent)
Description
  • When the output current of the inverter increases, the stall prevention (overcurrent) function is activated.
  • The following section explains about the stall prevention (overcurrent) function.
During acceleration When the output current (output torque under Real sensorless vector control or Vector control) of the inverter exceeds the stall prevention level (Pr.22 Stall prevention operation level, etc.), this function stops the increase in frequency until the overload current decreases to prevent the inverter from resulting in overcurrent trip. When the overload current is reduced below stall prevention operation level, this function increases the frequency again.
During constantspeed
operation
When the output current (output torque under Real sensorless vector control or Vector control) of the inverter exceeds the stall prevention level (Pr.22 Stall prevention operation level, etc.), this function reduces frequency until the overload current decreases to prevent the inverter from resulting in overcurrent trip. When the overload current is reduced below stall prevention operation level, this function increases the frequency up to the set value.
During deceleration When the output current (output torque under Real sensorless vector control or Vector control) of the inverter exceeds the stall prevention level (Pr.22 Stall prevention operation level, etc.), this function stops the decrease in frequency until the overload current decreases to prevent the inverter from resulting in overcurrent trip. When the overload current is reduced below stall prevention operation level, this function decreases the frequency again.
Check point
  • Check that the Pr.0 Torque boost setting is not too large.
  • The Pr.7 Acceleration time and Pr.8 Deceleration time settings may be too short.
  • Check that the load is not too heavy.
  • Check for any failures in peripheral devices.
  • Check that the Pr.13 Starting frequency is not too large.
  • Check that Pr.22 Stall prevention operation level is appropriate.
Corrective action
  • Gradually increase or decrease the Pr.0 setting by 1% at a time and check the motor status. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Set a larger value in Pr.7 and Pr.8. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • Reduce the load.
  • Try Advanced magnetic flux vector control, Real sensorless vector control, or Vector control.
  • Change the Pr.14 Load pattern selection setting.
  • The stall prevention operation current can be set in Pr.22 Stall prevention operation level. (Initial value is 150%.) 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. (Use Pr.156 to set either operation continued or not at OL operation.)

oL

Operation panel
indication
oL
FR-LU08 indication oL
Name Stall prevention (overvoltage)
Description
  • When the output voltage of the inverter increases, the stall prevention (overvoltage) function is activated.
  • The regeneration avoidance function is activated due to excessive regenerative power of the motor. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • The following section explains the stall prevention (overvoltage) function.
During deceleration If the regenerative power of the motor becomes excessive to exceed the regenerative power consumption capability, this function stops decreasing the frequency to prevent overvoltage trip. As soon as the regenerative power has reduced, deceleration resumes.
Check point
  • Check for sudden speed reduction.
  • Check if the regeneration avoidance function (Pr.882 to Pr.886) is being used. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
Corrective action The deceleration time may change. Increase the deceleration time using Pr.8 Deceleration time.

RB

Operation panel
indication
RB
FR-LU08 indication RB
Name Regenerative brake pre-alarm (Standard models only)
Description Appears if the regenerative brake duty reaches or exceeds 85% of the Pr.70 Special regenerative brake duty value. If the regenerative brake duty reaches 100%, a regenerative overvoltage (E. OV[ ]) occurs.
Check point
  • Check if the brake resistor duty is not too high.
  • Check that the Pr.30 Regenerative function selection and Pr.70 settings are correct.
Corrective action
  • Set the deceleration time longer.
  • Check the Pr.30 and Pr.70 settings. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))

TH

Operation panel
indication
TH
FR-LU08 indication TH
Name Electronic thermal relay function pre-alarm
Description Appears if the cumulative value of the electronic thermal O/L relay reaches or exceeds 85% of the preset level of Pr.9 Electronic thermal O/L relay. If the specified value is reached, the protection circuit is activated to shut off the inverter output.
Check point
  • Check for large load or sudden acceleration.
  • Check that the Pr.9 setting is appropriate. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
Corrective action
  • Reduce the load and frequency of operation.
  • Set an appropriate value in Pr.9. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))

PS

Operation panel
indication
PS
FR-LU08 indication PS
Name PU stop
Description
  • The motor is stopped using [STOP/RESET]key under the mode other than the PU operation mode. (To enable [STOP/RESET]key under the mode other than the PU operation mode, set Pr.75 Reset selection/disconnected PU detection/PU stop selection. Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
  • The motor is stopped by the emergency stop function.
Check point
  • Check for a stop made by pressing [STOP/RESET]key of the operation panel.
  • Check for whether the X92 signal is OFF.
Corrective action
  • Turn the start signal OFF and release with [PU/EXT]key.
  • Turn ON the X92 signal and OFF the start signal for release.

SL

Operation panel
indication
SL
FR-LU08 indication SL
Name Speed limit indication (output during speed limit)
Description Output if the speed limit level is exceeded during torque control.
Check point
  • Check that the torque command is not larger than required.
  • Check if the speed limit level is set too low.
Corrective action
  • Decrease the torque command value.
  • Increase the speed limit level.

CP

Operation panel
indication
CP
FR-LU08 indication CP
Name Parameter copy
Description Appears when parameter copy is performed between the FR-A820-03160(55K) or lower / FR-A840-01800(55K) or lower inverters and the FR-A820-03800(75K) or higher / FR-A840-02160(75K) or higher inverters.
Check point Resetting of Pr.9, Pr.30, Pr.51, Pr.56, Pr.57, Pr.61, Pr.70, Pr.72, Pr.80, Pr.82, Pr.90 to Pr.94, Pr.453, Pr.455, Pr.458 to Pr.462, Pr.557, Pr.859, Pr.860, and Pr.893 is necessary.
Corrective action Set the initial value in Pr.989 Parameter copy alarm release.

SA

Operation panel
indication
SA
FR-LU08 indication
Name Safety stop
Description Appears when safety stop function is activated (during output shutoff). (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
Check point
  • Check if an emergency stop device is activated.
  • Check if the shorting wire between S1 and PC or between S2 and PC is disconnected when not using the safety stop function.
Corrective action
  • An emergency stop device is active when using the safety stop function. Identify the cause of emergency stop, ensure the safety and restart the system.
  • When not using the safety stop function, short across terminals S1 and PC and across S2 and PC with shorting wire for the inverter to run.
  • If "[SA]" is indicated when wires across S1 and SIC and across S2 and SIC are both conducted while using the safety stop function (drive enabled), internal failure might be the cause. Check the wiring of terminals S1,S2, and SIC and contact your sales representative if the wiring has no fault.

MT1 to MT3

Operation panel
indication
MT1 to MT3
FR-LU08 indication MT1 to MT3
Name Maintenance signal output
Description Appears when the inverter's cumulative energization time reaches or exceeds the parameter set value. Set the time until the MT is displayed using Pr.504 Maintenance timer 1 warning output set time (MT1), Pr.687 Maintenance timer 2 warning output set time (MT2), and Pr.689 Maintenance timer 3 warning output set time (MT3). MT does not appear when the settings of Pr.504, Pr.687, and Pr.689 are initial values (9999).
Check point The set time of maintenance timer has been exceeded. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))
Corrective action Take appropriate countermeasures according to the purpose of the maintenance timer setting.
Setting "0" in Pr.503 Maintenance timer 1, Pr.686 Maintenance timer 2, and Pr.688 Maintenance timer 3 clears the indication.

UF

Operation panel
indication
UF
FR-LU08 indication UF
Name USB host error
Description Appears when an excessive current flows into the USB A connector.
Check point Check if a USB device other than a USB memory device is connected to the USB A connector.
Corrective action
  • If a device other than a USB memory device is connected to the USB A connector, remove the device.
  • Setting Pr.1049 USB host reset = "1" or inverter reset clears the UF indication.

HP1 to HP3

Operation panel
indication
HP1 to HP3
FR-LU08 indication HP1 to HP3
Name Home position return error
Description Appears when an error occurs during the home position return operation under position control. For the details, Refer to FR-A800 INSTRUCTION MANUAL (DETAILED) .
Check point Identify the cause of the error occurrence.
Corrective action Check the parameter setting, and check that the input signal is correct.

CF

Operation panel
indication
CF
FR-LU08 indication CF
Name Continuous operation during communication fault
Description Appears when the operation continues while an error is occurring in the communication line or communication
option (when Pr.502 = "4").
Check point
  • Check for a break in the communication cable.
  • Check for communication option faults.
Corrective action
  • Check the connection of communication cable.
  • Replace the communication option.

ED

Operation panel
indication
ED
FR-LU08 indication ED
Name Emergency drive in operation
Description Appears during emergency drive operation.
Check point Emergency drive operation is performed by turning ON the X84 signal.
Corrective action The display is cleared when the emergency drive operation ends. (Refer to FR-A800 INSTRUCTION MANUAL (DETAILED))

LDF

Operation panel
indication
LDF
FR-LU08 indication LDF
Name Load fault warning
Description Appears when the load is deviated from the detection width set in Pr.1488 Upper limit warning detection width or Pr.1489 Lower limit warning detection width.
Check point
  • Check if too much load is applied to the equipment, or if the load is too light.
  • Check that the load characteristics settings are correct.
Corrective action
  • Inspect the equipment.
  • Set the load characteristics (Pr.1481 to Pr.1487) correctly.

EHR

Operation panel
indication
EHR
FR-LU08 indication Fault
Name Ethernet communication fault
Description Appears when Ethernet communication is interrupted by physical factors while Pr.1431 Ethernet signal loss detection function selection = "1 or 2"
Check point
  • Check that the Ethernet board is installed onto the connector securely.
  • Check for a break in the Ethernet cable.
Corrective action
  • Connect the Ethernet board securely.
  • Check that the Ethernet cable is correctly connected to the Ethernet connector. Check that the Ethernet cable is not broken.