• When the Pr.72 PWM frequency selection setting is high, enable the ground fault detection at start.
• Because the detection is performed at start, output is delayed for approx. 20 ms every start.
• Use Pr.249 to enable/disable ground fault detection at operation start. Ground faults are detected always during operation
regardless of the Pr.249 setting.
Varying the activation level of the undervoltage
If the undervoltage protection (E.UVT) activates due to unstable voltage in the power supply, the undervoltage level (DC bus
voltage value) can be changed.
For the 200 V class
For the 400 V class
• Do not use this function when switching to an external battery, since the inrush current when power is restored increases, as
the undervoltage level is decreased.
• For the 200 V class inverters, the setting is available for the FR-F820-02330(55K) or lower.
• The Pr.598 setting is valid for induction motors. When either of the first or second motor is a PM motor, the Pr.598 setting is
Initiating a protective function
A fault (protective function) is initiated by setting the parameter.
This function can be used to check how the system operates at activation of a protective function.
• To initiate a fault (protective function), set the assigned number of the protective function to be initiated in Pr.997.
• The value set in Pr.997 is not stored in EEPROM.
• When a protective function activates, the inverter output is shut off, a fault is displayed, and a fault signal (ALM, ALM2) is
• The latest fault in the fault history is displayed while the fault initiation function is in operation. After a reset, the fault history
goes back to the previous status. (The protective function generated by the fault is not saved in the fault history.)
• Perform inverter reset to cancel the protective function.
• For the selectable parameter by Pr.997 and the corresponding protective functions, refer to
• If a protective function is already operating, no fault can be activated by Pr.997.
• The retry function is disabled when a protective function has been initiated by the fault initiation function.
• If a fault occurs after a protective function has been activated, the protective function indication does not change. The fault is
not saved in the fault history either.
I/O phase loss protection selection
The output phase loss protection function, which stops the inverter output if one of the three phases (U, V, W) on the inverter's
output side (load side) is lost, can be disabled.
5.7 (H) Protective function parameter
16 to 253
175 to 215 VDC
Set the DC voltage value at which E.UVT occurs.
350 to 430 VDC
E.UVT occurs at 215 VDC (200 V class) / 430 VDC (400
The setting range is same with the one for fault data codes of the
inverter (which can be read through communication). Written data is not
stored in EEPROM.
The read value is always "9999". The protective function is not
activated with this setting.