Mitsubishi Electric FR-F740-00023 Instruction Manual page 284

Operation Panel
Indication
Name
Regenerative overvoltage trip during acceleration
If regenerative energy causes the inverter's internal main circuit DC voltage to reach or exceed the
Description
specified value, 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.
1. Check for too slow acceleration. (e.g. during descending acceleration with lifting load)
Check point
2. Check that the Pr. 22 Stall prevention operation level is not lower than the no load current.
1. · Decrease the acceleration time.
Corrective action
2. Set a value larger than the no load current in Pr. 22 Stall prevention operation level.
Operation Panel
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
Description
specified value, 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.
1. Check for sudden load change.
Check point
2. Check that the Pr. 22 Stall prevention operation level is not lower than the no load current.
1. · Keep load stable.
Corrective action
2. Set a value larger than the no load current in Pr. 22 Stall prevention operation level.
Operation Panel
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
Description
specified value, 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 to Pr. 886). (Refer to the
· Use the brake unit or power regeneration common converter (FR-CV) as required.
Operation Panel
Indication
Name Inverter overload trip (electronic thermal relay function)
If a current not less than 110%
Description
(170% or less), the electronic thermal relay activates to stop the inverter output in order to protect the
output transistors. (Overload capacity 110%
· 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.
· 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.
*1 Resetting the inverter initializes the internal thermal integrated data of the electronic thermal relay function.
*2 120% when LD is selected
E.OV1
· Use regeneration avoidance function (Pr. 882 to Pr. 886).
(Refer to page 248.)
E.OV2
· Use regeneration avoidance function (Pr. 882 to Pr. 886).
(Refer to the page 248.)
· Use the brake unit or power regeneration common converter (FR-CV) as required.
E.OV3
E.THT
of the rated output current flows and overcurrent trip does not occur
*2
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
page 248.)
FR-PU04
Inv. Overload
FR-PU07
*1
60s inverse-time characteristic)
*2
5
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