Mitsubishi Electric FR-D720S SC EC Instruction Manual page 449

Troubleshooting
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
Operation Panel
Indication
Name
Description
Check point
Corrective action
FR-D700 SC EC
E.BE
Brake transistor alarm detection/internal circuit error
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.
In this case, the inverter must be powered off immediately.
Reduce the load inertia.
Check that the frequency of using the brake is proper.
Check that the brake resistor selected is correct.
Replace the inverter.
E.GF
Output side earth (ground) fault overcurrent protection
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) fault detection at start".
Check for an earth fault in the motor and connection cable.
Remedy the earth fault portion.
E.LF
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 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 protec-
tion selection".
Check the wiring (Check that the motor is normal.)
Check that the capacity of the motor used is not smaller than that of the inverter.
Wire the cables properly.
Check the Pr. 251 "Output phase failure protection selection" setting.
E.OHT
External thermal relay operation
If the external thermal relay provided for motor overheat protection or the internally
mounted temperature relay in the motor, etc. switches on (contacts open), the inverter out-
put is stopped.
Functions when "7" (OH signal) is set to any of Pr. 178 to Pr. 182 "Input terminal function
selection". This protective function does not function in the initial status (OH signal is not
assigned).
Check for motor overheating.
Check that the value of "7" (OH signal) is set correctly in any of Pr. 178 to Pr. 182 "Input
terminal function selection".
Reduce the load and frequency of operation.
Even if the relay contacts are reset automatically, the inverter will not restart unless it is
reset.
Causes and corrective actions
FR-PU04
Br. Cct. Fault
FR-PU07
FR-PU04
Ground Fault
FR-PU07
FR-PU04
E.LF
FR-PU07
FR-PU04
OH Fault
FR-PU07
7 - 13