Mitsubishi Electric FR-A500 Instruction Manual page 209

Operation Panel
Indication
Name Stall prevention (overvoltage)
During
Description
deceleration
Check point Check for sudden speed reduction.
The deceleration time may change. Increase the deceleration time using Pr. 8
Corrective action
"deceleration time".
Operation Panel
Indication
Name PU stop
A stop made by pressing the
Description
stop selection".
Check for a stop made by pressing the
Check point
Corrective action Refer to page 106.
Operation Panel
Indication
Name Regenerative brake prealarm
This alarm appears if the regenerative brake duty reaches 85% of the value set in
Pr. 70 "special regenerative brake duty".
Description
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
Electronic overcurrent protection prealarm
Name
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
Description
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
This alarm appears if:
• The RES signal is on.
• You attempted to set any parameter value in external operation mode.
• You attempted to change the operation mode during operation.
• You attempted to set any parameter value outside its setting range.
Description
• Normal communication cannot be made between the PU and inverter.
• You attempted to set any parameter value during operation
• You attempted to make parameter setting when Pr. 77 "parameter write disable
Corrective action Perform operation correctly.
oL
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.
PS
RB
TH
Err.
(while signal STF or STR is ON).
selection" has been set to disable parameter write.
PROTECTIVE FUNCTIONS
FR-PU04
FR-PU04
key of the PU has been set in Pr. 75 "PU
STOP
RESET
key of the operation panel.
STOP
RESET
FR-PU04
FR-PU04
200
oL
PS
RB
TH