Mitsubishi Electric 700 Series Instruction Manual page 202

Operation panel
EV
indication
Name 24V external power supply operation
Description Flickers when the main circuit power supply is OFF and the 24V external power is being supplied.
Check if the 24V external power is supplied.
Check point Check if the (main circuit) power supply for the inverter is ON. Check if the voltage is low.
Check if the jumper between terminal P/+ and P1 is removed.
Turn ON the power supply for the inverter (main circuit).
If
Corrective action
supplied, check the power supply (for the main circuit).
Check if the jumper is installed securely between the terminal P/+ and P1.
(3) Alarm
When an alarm occurs, the output is not shut off.
Operation panel
FN
indication
Name
Fan alarm
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 230% of the rated current during acceleration, the
Description
protective circuit is activated and the inverter trips.
Check for sudden acceleration.
Check that the downward acceleration time is not long for lifts.
Check for output short-circuit/ground fault.
Check that the Pr. 3 Base frequency setting is not 60Hz when the motor rated frequency is 50Hz.
Check point
Check if the stall prevention operation level is set too high.
Check if the fast-response current limit operation is disabled.
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.)
Increase the acceleration time. (Shorten the downward acceleration time for lifts.)
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.
Check the wiring to make sure that output short circuit/ground fault does not occur.
Corrective action
Set 50Hz in Pr. 3 Base frequency. (Refer to page 107)
Lower the setting of stall prevention operation level. (Refer to page 101).
Activate the fast-response current limit operation.
Set base voltage (rated voltage of the motor, etc.) in Pr. 19 Base frequency voltage. (Refer to page 107)
Operation panel
E.OC2
indication
Name
Overcurrent trip during constant speed
When the inverter output current reaches or exceeds approximately 230% of the rated current during constant speed
Description
operation, the protective circuit is activated and the inverter trips.
Check for sudden load change.
Check for output short-circuit/ground fault.
Check point
Check if the stall prevention operation level is set too high.
Check if the fast-response current limit operation is disabled.
Keep load stable.
Check the wiring to make sure that output short circuit/ground fault does not occur.
Corrective action
Lower the setting of stall prevention operation level. (Refer to page 101).
Activate the fast-response current limit operation.
appears by turning ON the power supply of the inverter (main circuit) while the external 24V power is
Causes and corrective actions
appears on the operation panel when the cooling fan stops due to
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