Mitsubishi FR-A500 Series - Page 204

PROTECTIVE FUNCTIONS
190
Operation Panel
Indication
oL
FR-PU04
oL
Name
Stall prevention (overvoltage)
Description
During
deceleration
If the regenerative energy of the motor increases too much to
exceed the brake capability, this function stops the decrease
in frequency to prevent overvoltage shut-off. As soon as the
regenerative energy has reduced, deceleration resumes.
Check point
Check for sudden speed reduction.
Corrective action
The deceleration time may change. Increase the deceleration time using Pr. 8
"deceleration time".
Operation Panel
Indication
PS
FR-PU04
PS
Name
PU stop
Description
A stop made by pressing the
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STOP
RESET
key of the PU has been set in Pr. 75 "PU
stop selection".
Check point
Check for a stop made by pressing the
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STOP
RESET
key of the operation panel.
Corrective action
Refer to page 100.
Operation Panel
Indication
RB
FR-PU04
RB
Name
Regenerative brake prealarm
Description
This alarm appears if the regenerative brake duty reaches 85% of the value set
in Pr. 70 "special regenerative brake duty".
Regenerative overvoltage (E.OV_) occurs if the regenerative brake duty reaches
100%.
Check point
Check that the brake resistor is not used frequently.
Corrective action
Increase the deceleration time.
Operation Panel
Indication
TH
FR-PU04
TH
Name
Electronic overcurrent protection prealarm
Description
This alarm appears if the cumulative value of the electronic overcurrent
protection reaches 85% of the preset level. If it reaches 100% of the preset level,
motor overload shutoff (E.THM) occurs.
Check point
Check for large load or sudden acceleration.
Corrective action
Reduce the load volume or the frequency of operation.
Operation Panel
Indication
Err.
Description
This alarm appears if:
•
The RES signal is on.
•
You attempted to set any parameter value in the external operation mode.
•
You attempted to change the operation mode during operation.
•
You attempted to set any parameter value outside its setting range.
•
Normal communication cannot be made between the PU and inverter.
•
You attempted to set any parameter value during operation
(while signal STF or STR is ON).
•
You attempted to make parameter setting when Pr. 77 "parameter write disable
selection" has been set to disable parameter write.
Corrective action
Perform operation correctly.