Operation Panel Indication: E. OV3 FR-PU04 OV During Dec

    Name: Regenerative overvoltage shut-off during deceleration or stop

    Description: If regenerative energy causes the inverter's internal main circuit DC voltage to reach or exceed the specified value, the protective circuit is activated to stop the inverter output. It may also be activated by a surge voltage generated in the power supply system.

    Check Point: Check for sudden speed reduction.

    Corrective Action: Increase the deceleration time (set the deceleration time which matches the inertia moment of the load). Decrease the braking duty. Use the brake unit or high power factor converter (FR-HC) as required.

    Operation Panel Indication: E. THM FR-PU04 Motor Overload

    Name: Motor overload shut-off (electronic overcurrent protection)

    Description: The electronic overcurrent protection in the inverter detects motor overheat due to overload or reduced cooling capability during constant-speed operation to stop the inverter output. When a multi-pole motor or two or more motors are run, provide a thermal relay on the output side of the inverter.

    Check Point: Check the motor for use under overload.

    Corrective Action:
+ Reduce the load weight.
+ For the constant-torque motor, change the Pr. 71 setting to the constant-torque motor setting.

    Operation Panel Indication: E. THT FR-PU04 Inv. Overload

    Name: Inverter overload shut-off (electronic overcurrent protection)

    Description: If a current of more than 150% of the rated output current flows and overcurrent shut-off does not occur (200% or less), inverse-time characteristics cause the electronic overcurrent protection to be activated to stop the inverter output in order to protect the output transistors.

    Check Point: Check the motor for use under overload.

    Corrective Action: Reduce the load weight.

Note: Resetting the inverter initializes the internal heat integrating data of the electronic overcurrent protection.


    Operation Panel Indication: E. FIN FR-PU04 H/Sink O/Temp

    Name: Fin overheat

    Description: If the cooling fin overheats, the overheat sensor is actuated to stop the inverter output.

+ Check for too high ambient temperature.
+ Check for cooling fin clogging.

    Corrective Action: Set the ambient temperature to within the specifications.


    Operation Panel Indication: E. BE FR-PU04 Br. Cct. Fault (Note)

    Name: Brake transistor alarm detection (Note 2)

    Description: If a brake transistor fault occurs due to excessively large regenerative energy from the motor, for example, that fault is detected to stop the inverter output. In this case, the inverter power must be switched off immediately.

    Check Point: Check for improper braking duty.

    Corrective Action: Change the inverter. Please contact your sales representative.

Note: This function is activated only when the optional brake resistor is connected.

    Operation Panel Indication: E. GF FR-PU04 Ground Fault

    Name: Output side ground fault overcurrent protection

    Description: This function stops the inverter output if a ground fault overcurrent flows due to a ground fault that occurred in the inverter's output (load) side.

    Check Point: Check for a ground fault in the motor and connection cable.

    Corrective Action: Remedy the ground fault portion.

    Operation Panel Indication: E. OHT FR-PU04 OH Fault

    Name: External thermal relay operation (Note 3)

    Description: If the external thermal relay designed for motor overheat protection or the internally mounted temperature relay in the motor switches on (contacts open), the inverter output is stopped. If the relay contacts are reset automatically, the inverter will not restart unless it is reset.

+ Check for motor overheating.
+ Check that the value of 7 (OH signal) is set correctly in any of Pr. 180 to Pr. 183 (input terminal function selection).

    Corrective Action: Reduce the load and operating duty.

Note: This function is activated only when OH has been set to any of Pr. 180 to Pr. 183 (input terminal function selection).

    Operation Panel Indication: E. OLT FR-PU04 Stall Prev STP

    Name: Stall prevention

    Description: The running frequency has fallen to 0 by stall prevention activated. (OL while stall prevention is being activated.)

    Check Point: Check the motor for use under overload.

    Corrective Action: Reduce the load weight.


    Operation Panel Indication: E. OPT FR-PU04 Option Fault

    Name: Option alarm (Note 4)

    Description: Stops the inverter output if a functional fault (e.g. communication error of the communication option) occurs in the communication option. Stops the inverter output if the inverter station is disconnected from the system in the NET mode.

+ Check that the communication cable is not open.
+ Check that the PU connector is plugged securely.

+ Please contact your sales representative.
+ Securely plug the PU connector.

Note: During NET mode communication, alarm "E. OPT" indicates the "E. PUE" error. Refer to "E. PUE".

    Operation Panel Indication: E. PE FR-PU04 Corrupt Memory

    Name: Parameter storage device alarm

    Description: A fault occurred in parameters stored (example: E2 PROM fault).

    Check Point: Check for too many number of parameter write times.

    Corrective Action: Please contact your sales representative.

    Operation Panel Indication: E. PUE FR-PU04 PU Leave Out

    Name: Parameter unit disconnection

    Description: This function stops the inverter output if communication between the inverter and PU is suspended, e.g. the PU is disconnected when "2", "3", "16", or "17" was set in Pr. 75. This function stops the inverter output if the number of successive communication errors is greater than the number of permissible retries when the Pr. 121 value is other than "9999" for RS-485 communication from the PU connector.

+ Check for loose fitting of the control panel (FR-PA02-02) or FR-PU04.
+ Check the Pr. 75 setting.

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