Mitsubishi Electric FR-D720-008 Instruction Manual page 255

Operation panel
SA
indication
Name Safety stop
Description Appears when safety stop function is activated (during output shutoff).
If the indication appears when safety stop function is not used, check that shorting wires between S1 and SC, S2 and
Check point
SC are connected.
If the indication appears when safety stop function is not used, short between S1 and SC, S2 and SC with shorting
Corrective action
wires.
(3) Alarm
When an alarm occurs, the output is not shut off. You can also output an alarm signal by making parameter setting.
(Set "98" in Pr. 190 or Pr. 192 (output terminal function selection). Refer to page 117 ).
Operation panel
FN
indication
Name
Fan fault
For the inverter that contains a cooling fan,
Description
an alarm or different operation from the setting of Pr. 244 Cooling fan operation selection.
Check point Check the cooling fan for an alarm.
Corrective action Check for fan alarm. Please contact your sales representative.
(4) Fault
When a fault occurs, the inverter trips and a fault signal is output.
Operation panel
E.OC1
indication
Name
Overcurrent trip during acceleration
When the inverter output current reaches or exceeds approximately 200% of the rated current during acceleration, the
Description
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.
Check point
4. Check that the Pr. 3 Base frequency setting is not 60Hz when the motor rated frequency is 50Hz.
5. Check that stall prevention operation is appropriate.
6. 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 increase in motor current.)
1. Increase the acceleration time. (Shorten the downward acceleration time in vertical lift application.)
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.
Corrective action 3. Check the wiring to make sure that output short circuit/ground fault does not occur.
4. Set 50Hz in Pr. 3 Base frequency. (Refer to page 83)
5. Perform stall prevention operation appropriately. (Refer to page 77).
6. Set base voltage (rated voltage of the motor, etc.) in Pr. 19 Base frequency voltage. (Refer to page 83)
Operation panel
E.OC2
indication
Name
Overcurrent trip during constant speed
When the inverter output current reaches or exceeds approximately 200% of the rated current during constant speed
Description
operation, the protective circuit is activated and the inverter trips.
1. Check for sudden load change.
Check point
2. Check for output short-circuit/ground fault.
3. Check that stall prevention operation is appropriate.
1. Keep load stable.
Corrective action 2. Check the wiring to make sure that output short circuit/ground fault does not occur.
3. Perform stall prevention operation appropriately. (Refer to page 77).
Causes and corrective actions
FR-PU04
——
FR-PU07
FR-PU04
FN
FR-PU07
appears on the operation panel when the cooling fan stops due to
FR-PU04
OC During Acc
FR-PU07
FR-PU04
Stedy Spd OC
FR-PU07
5
251