MITSUBISHI ELECTRIC FR-S520E - Manual (Page 171)

161
Errors (Alarms)
3
PROT
ECT
IVE F
UNCT
IONS
3.1.1 Error (alarm) definitions
(1) Major failures
When the protective function is activated, the inverter output is shut off and the alarm
is output.
Operation Panel Indication OC1 FR-PU04 OC During Acc
Name Overcurrent shut-off during acceleration
Description
When the inverter output current reaches or exceeds
approximately 200% of the rated inverter current during
acceleration, the protective circuit is activated to stop the inverter
output.
Check point
Check for sudden acceleration.
Check that the downward acceleration time is not long in vertical
lift application.
Check for output short-circuit/earth (ground) fault.
Corrective action
Increase the acceleration time.
Shorten the downward acceleration time in vertical lift application.
Operation Panel Indication OC2 FR-PU04 Stedy Spd OC
Name Overcurrent shut-off during constant speed
Description
When the inverter output current reaches or exceeds
approximately 200% of the rated inverter current during constant-
speed operation, the protective circuit is activated to stop the
inverter output.
Check point
Check for sudden load change.
Check for output short-circuit/earth (ground) fault.
Corrective action Keep load stable.
Operation Panel Indication OC3 FR-PU04 OC During Dec
Name Overcurrent shut-off during deceleration
Description
When the inverter output current reaches or exceeds
approximately 200% of the rated inverter current during
deceleration (other than acceleration or constant speed), the
protective circuit is activated to stop the inverter output.
Check point
Check for sudden speed reduction.
Check for output short-circuit/earth (ground) fault.
Check for too fast operation of motor's mechanical brake.
Corrective action
Increase the deceleration time.
Adjust brake operation.