Mitsubishi Electric FR-E700 Instruction Manual page 537

Troubleshooting
Fault
When a fault occurs, the inverter trips and a fault signal is output.
Operation panel
indication
Name
Description
Check point
Corrective action
Operation panel
indication
Name
Description
Check point
Corrective action
Operation panel
indication
Name
Description
Check point
Corrective action
FR-E700 SC EC/ENE
E.OC1
Overcurrent shut-off during acceleration
When the inverter output current reaches or exceeds approximately 230% of the rated current
during acceleration, the protective circuit is activated and the inverter trips.
1) Check for sudden acceleration.
2) Check that the downward acceleration time is not long in vertical lift application.
3) Check for output short circuit/ground fault.
4) Check if the stall prevention operation level is set too high.
Check if the fast-response current limit operation is disabled.
5) Check that regeneration is not performed frequently. (Check that the output voltage becomes
larger than the V/F reference value at regeneration and overcurrent occurs due to the high
voltage.)
1) Increase the acceleration time. (Shorten the downward acceleration time in vertical lift appli-
cation.)
2) When "E.OC1" is always lit at starting, disconnect the motor once and start the inverter. If
"E.OC1" is still lit, contact your sales representative.
3) Check the wiring to make sure that output short circuit/ground fault does not occur.
4) Lower the setting of stall prevention operation level (Refer to section 6.3.5).
Activate the fast-response current limit operation. (Refer to section 6.3.5).
5) Set base voltage (rated voltage of the motor, etc.) in Pr. 19 "Base frequency voltage". (Refer to
section 6.5.1.)
E.OC2
Overcurrent shut-off during constant speed
When the inverter output current reaches or exceeds approximately 230% of the rated current
during constant speed operation, the protective circuit is activated and the inverter trips.
1) Check for sudden load change.
2) Check for output short circuit/ground fault.
3) Check if the stall prevention operation level is set too high.
Check if the fast-response current limit operation is disabled.
1) Keep load stable.
2) Check the wiring to make sure that output short circuit/ground fault does not occur.
3) Lower the setting of stall prevention operation level (Refer to section 6.3.5).
Activate the fast-response current limit operation. (Refer to section 6.3.5).
E.OC3
Overcurrent shut-off during deceleration or stop
When the inverter output current reaches or exceeds approximately 230% of the rated inverter
current during deceleration (other than acceleration or constant speed), the protective circuit is
activated and the inverter trips.
1) Check for sudden speed reduction.
2) Check for output short circuit/ground fault.
3) Check for too fast operation of the motor's mechanical brake.
4) Check if the stall prevention operation level is set too high.
Check if the fast-response current limit operation is disabled.
1) Increase the deceleration time.
2) Check the wiring to make sure that output short circuit/ground fault does not occur.
3) Check the mechanical brake operation.
4) Lower the setting of stall prevention operation level (Refer to section 6.3.5).
Activate the fast-response current limit operation. (Refer to section 6.3.5).
Causes and corrective actions
FR-PU04
OC During Acc
FR-PU07
FR-PU04
OC During Dec
FR-PU07
FR-PU04
OC During Dec
FR-PU07
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