Mitsubishi Electric FR-D720-0.1K Instruction Manual page 310

Operation panel
indication
Name
Description
Check point
Corrective action
Operation panel
indication
Name
Description
Check point
Corrective action
●SERIAL number check
Check the SERIAL number indicated on the inverter rating plate or package.
Refer to the inverter manual for the location of the rating plate.
Rating plate example
 4
Symbol Year
The SERIAL consists of 1 version symbol, 2 numeric characters or 1 numeric character and 1 alphabet letter
indicating year and month, and 6 numeric characters indicating control number.
Last digit of the production year is indicated as the Year, and the Month is indicated by 1 to 9, X (October), Y
(November), and Z (December).
E.OV2
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, 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 that the setting of Pr. 22 Stall prevention operation level is not too small.
 Check if the stall prevention operation is frequently activated in an application
with a large load inertia.
 Keep load stable.
 Use regeneration avoidance function (Pr. 882, Pr. 883, Pr. 885, Pr. 886). (
Chapter 4 of the Instruction Manual (Applied).)
 Use the brake resistor, brake unit or power regeneration common converter (FR-CV)
as required.
 Set the Pr.22 Stall prevention operation level correctly.
 Set Pr.154 Voltage reduction selection during stall prevention operation = "11".
E.OV3
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, 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 speed reduction.
 Check if the stall prevention operation is frequently activated in an application
with a large load inertia.
 Increase the deceleration time. (Set the deceleration time which matches the moment
of inertia of the load)
 Make the brake cycle longer.
 Use regeneration avoidance function (Pr. 882, Pr. 883, Pr. 885, Pr. 886). (
Chapter 4 of the Instruction Manual (Applied).)
 Use the brake resistor, brake unit or power regeneration common converter (FR-CV)
as required.
 Set Pr.154 Voltage reduction selection during stall prevention operation = "11".
3 
Month Control number
SERIAL (Serial No.)
FR-PU04
FR-PU07
FR-PU04
FR-PU07
2/4
Stedy Spd OV
Refer to
OV During Dec
Refer to
BCN-C22005-689