Mitsubishi Electric 700 Series Instruction Manual page 205

Causes and corrective actions
Operation panel
E.OLT
indication
Name
Stall prevention stop stop
If the output frequency has fallen to 1Hz by stall prevention operation and remains for 3s, a fault (E.OLT) appears and
Description
trips the inverter. OL appears while stall prevention is being activated.
E.OLT may not occur if stall prevention (OL) is activated during output phase loss.
Check point Check the motor for use under overload. (Refer to page 102).
Corrective action Reduce the load weight. (Check the Pr. 22 Stall prevention operation level setting.)
Operation panel
E.BE
indication
Name
Brake transistor alarm detection
When a brake transistor alarm has occurred due to the large regenerative energy from the motor etc., the brake
transistor alarm is detected and the inverter trips.
Description
In this case, the inverter must be powered OFF immediately.
Reduce the load inertia.
Check point
Check that the frequency of using the brake is proper.
Corrective action Replace the inverter.
Operation panel
E.GF
indication
Name Output side earth (ground) fault overcurrent at start
The inverter trips if an earth (ground) fault overcurrent flows at start due to an earth (ground) fault that occurred on
the inverter's output side (load side). Whether this protective function is used or not is set with Pr. 249 Earth (ground)
Description
fault detection at start. When the setting of Pr. 249 Earth (ground) fault detection at start is the initial value (Pr. 249 ="0"),
this warning does not occur.
Check point
Check for a ground fault in the motor and connection cable.
Corrective action
Remedy the ground fault portion.
Operation panel
E.LF
indication
Name Output phase loss
If one of the three phases (U, V, W) on the inverter's output side (load side) is lost during inverter operation (except
Description during DC injection brake operation and when output frequency is under 1Hz), inverter stops the output. Whether the
protective function is used or not is set with Pr. 251 Output phase loss protection selection.
Check the wiring. (Check that the motor is normal.)
Check point
Check that the capacity of the motor used is not smaller than that of the inverter.
Wire the cables properly.
Corrective action
Check the Pr. 251 Output phase loss protection selection setting.
Operation panel
E.OP1
indication
Name Communication option fault
Description Inverter output is stopped when a fault occurs on the communication line of FL remote communication.
Check if the inverter's LED shows any fault.
Check point
Check if the FL-net dedicated cable has a break.
Check if the length of the FL-net dedicated cable is within the specified range.
Refer to "Troubleshooting in FL remote communication" on page 209, and take corrective actions for the fault.
Corrective action Check the connection of the FL-net dedicated cable.
Check that each FL-net dedicated cable length between nodes is within the specified range. (Refer to page 46).
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