Mitsubishi Electric FR-A700 Instruction Manual page 733

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-A700 EC
E.ILF
Input phase failure
This alarm is output when function valid setting (=1) is set in Pr. 872 "Input phase failure
protection selection" and one phase of the three phase power input opens. (Refer to
section 6.17.3.)
Check for a brake in the cable for the three-phase power supply input.
Wire the cables properly.
Repair a brake portion in the cable.
Check the Pr. 872 "Input phase failure protection selection" setting.
E.OLT
Stall prevention
If the frequency has fallen to 0.5Hz by stall prevention operation and remains for 3s, an
alarm (E.OLT) appears to shutoff the inverter output. OL appears while stall prevention is
being activated.
When speed control is performed by real sensorless vector control or vector control, an
alarm (E.OLT) is displayed and the inverter output is stopped if frequency drops to the Pr.
865 "Low speed detection" (initial value is 1.5Hz) setting by torque limit operation and the
output torque exceeds Pr. 874 "OLT level setting" (initial value is 150%) setting and
remains for more than 3s.
Check the motor for use under overload. (Refer to section 6.7.4).
Check that the Pr. 865 "Low speed detection" and Pr. 874 OLT level setting values are
correct. (Check the Pr. 22 "Stall prevention operation level" setting if V/F control is
exercised.)
Reduce the load weight.
Change the Pr. 22 "Stall prevention operation level", Pr. 865 "Low speed detection" and
Pr. 874 "OLT level setting" values. (Check the Pr. 22 "Stall prevention operation level"
setting if V/F control is exercised.)
E.GF
Output side earth fault over current protection
This function stops the inverter output if an earth fault over current flows due to an earth
(ground) fault that occurred on the inverter's output (load) side.
Check for an earth fault in the motor and connection cable.
Remedy the earth fault portion.
E.LF
Output phase failure protection
This function stops the inverter output if one of the three phases (U, V, W) on the inverter's
output side (load side) opens.
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.
Causes and corrective actions
FR-PU04 Fault 14
FR-PU07 Input phase loss
FR-PU04
Stall Prev STP ( OL shown during
stall prevention operation)
FR-PU07
FR-PU04
Ground Fault
FR-PU07
FR-PU04
—
FR-PU07
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