Mitsubishi Electric 800 Series, Instruction Manual, Page: 326 / 727

(H) Protective function parameter
PARAMETERS
325
5
GROUP
H
5.10.4
Earth (ground) fault detection at start
• If a ground fault is detected at start while Pr.249 = "1", the output-side earth (ground) fault overcurrent (E.GF) is displayed
and the outputs are shut off. (Refer to page 640 )
• The Pr.249 setting is enabled during V/F control and Advanced magnetic flux vector control
• When the Pr.72 PWM frequency selection selection setting is high, enable the ground fault detection at start.
NOTE
• Because of the detection performed at start, the output is delayed by approximately 20 ms at 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.
5.10.5
Initiating a protective function
• To initiate a fault (protective function), set the assigned number of the protective function you want to initiate in Pr.997 .
• The value set in Pr.997 is not stored in EEPROM.
• When a protective function activates, the inverter trips, a fault is displayed, and a fault signal (ALM, ALM2) is output.
• 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 page 629 .
NOTE
• 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.
Select whether to enable/disable earth (ground) fault detection at start. When enabled, earth (ground) fault detection is
performed immediately after a start signal input to the inverter.
Pr. Name Initial value Setting range Description
249
H101 Earth (ground) fault
detection at start
0
0 Without the earth (ground) fault detection at start
1 With the earth (ground) fault detection at start
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.
Pr. Name
Initial
value Setting
range
Description
997
H103
Fault initiation
9999
16 to 253
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.
9999
The read value is always "9999".
With this setting, the protective function does not activate.
V/F V/F V/F Magnetic flux Magnetic flux Magnetic flux