Mitsubishi FREQROL-E700, Manual

Page: 97 / 108

App.2-3
Appendix
Function name Description Corrective action Display
Major
fault
Overcurrent
trip during
acceleration
Overcurrent has occurred
during acceleration.
• Set the acceleration time longer. (Shorten the
downward acceleration time in vertical lift application.)
• If "E.OC1" always appears at start, disconnect the
motor once and restart the inverter. If "E.OC1" still
appears, the inverter may be faulty. Contact your sales
representative.
• Check the wiring for output short circuit and ground fault.
• When the rated motor frequency is 50Hz, set the Pr. 3
Base frequency to 50Hz.
• Lower the stall prevention operation level.
• Activate the stall prevention operation and the fast-
response current limit operation. (Pr.156)
• For the operation with frequent regenerative driving,
set the base voltage (rated motor voltage, etc.) in Pr.
19 Base frequency voltage.
• If the motor is coasting, stop the motor, then input a
start command. Alternatively, use the automatic restart
after instantaneous power failure/flying start function.
Overcurrent
trip during
constant
speed
Overcurrent has occurred
during constant speed
operation.
• Keep the load stable.
• Check the wiring to avoid output short circuit or ground
fault.
• Lower the stall prevention operation level.
• Activate the stall prevention operation and the fast-
response current limit operation. (Pr.156)
Overcurrent
trip during
deceleration
or stop
Overcurrent has occurred
during deceleration or at a
stop.
• Set the deceleration time longer.
• Check the wiring to avoid output short circuit or ground
fault.
• Check if the mechanical brake is set to be activated
too early.
• Lower the stall prevention operation level.
• Activate the stall prevention operation and the fast-
response current limit operation. (Pr.156)
Regenerative
overvoltage
trip during
acceleration
Overvoltage has occurred
during acceleration.
• Set the acceleration time shorter.
• Use the regeneration avoidance function (Pr. 882, Pr.
883, Pr.885, Pr.886).
• Set the Pr. 22 Stall prevention operation level correctly.