Mitsubishi Electric FR-E720-0.1K(SC) Instruction Manual page 297

Operation panel
E.OV1
indication
Name Regenerative overvoltage trip during acceleration
If regenerative energy causes the inverter's internal main circuit DC voltage to reach or exceed the specified value,
Description the protective circuit is activated and the inverter trips. The circuit may also be activated by a surge voltage produced
in the power supply system.
Check for too slow acceleration. (e.g. during downward acceleration in vertical lift load)
Check point
Check that the setting of Pr. 22 Stall prevention operation level is not too small.
Decrease the acceleration time.
Corrective action
Check that regeneration avoidance function (Pr. 882, Pr. 883, Pr. 885, Pr. 886) is used. (Refer to page 261).
Set the Pr.22 Stall prevention operation level correctly.
Operation panel
E.OV2
indication
Name Regenerative overvoltage trip during constant speed
If regenerative energy causes the inverter's internal main circuit DC voltage to reach or exceed the specified value,
Description
the protective circuit is activated to stop the inverter output. The circuit may also be activated by a surge voltage
produced in the power supply system.
Check for sudden load change.
Check point
Check that the setting of Pr. 22 Stall prevention operation level is not too small.
Keep load stable.
Check that regeneration avoidance function (Pr. 882, Pr. 883, Pr. 885, Pr. 886) is used. (Refer to page 261).
Corrective action
Use the brake resistor, brake unit or power regeneration common converter (FR-CV) as required.
Set the Pr.22 Stall prevention operation level correctly.
Operation panel
E.OV3
indication
Name Regenerative overvoltage trip during deceleration or stop
If regenerative energy causes the inverter's internal main circuit DC voltage to reach or exceed the specified value,
Description
the protective circuit is activated to stop the inverter output. The circuit may also be activated by a surge voltage
produced in the power supply system.
Check point
Check for sudden speed reduction.
Increase the deceleration time. (Set the deceleration time which matches the moment of inertia of the load)
Longer the brake cycle.
Corrective action
Use regeneration avoidance function (Pr. 882, Pr. 883, Pr. 885, Pr. 886). (Refer to page 261).
Use the brake resistor, brake unit or power regeneration common converter (FR-CV) as required.
Operation panel
E.THT
indication
Name Inverter overload trip (electronic thermal relay function)
If the temperature of the output transistor element exceeds the protection level under the condition that a current not
Description
less than the rated inverter current flows and overcurrent trip does not occur (230% or less), the electronic thermal
relay activates to stop the inverter output. (Overload capacity 150% 60s, 200% 3s)
Check that acceleration/deceleration time is not too short.
Check that torque boost setting is not too large (small).
Check point Check that load pattern selection setting is appropriate for the load pattern of the using machine.
Check the motor for use under overload.
Check for too high surrounding air temperature.
Increase acceleration/deceleration time.
Adjust the torque boost setting.
Corrective action Set the load pattern selection setting according to the load pattern of the using machine.
Reduce the load weight.
Set the surrounding air temperature to within the specifications.
Causes and corrective actions
FR-PU04
OV During Acc
FR-PU07
FR-PU04
Stedy Spd OV
FR-PU07
FR-PU04
OV During Dec
FR-PU07
FR-PU04
Inv. Overload
FR-PU07
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