FujiFilm Frenic-Mini Instruction Manual page 129

OUn
[ 2 ] Overvoltage protection
Problem The DC link circuit voltage was over the detection level of overvoltage.
OU1
OU2
OU3
Possible Causes
(1) The power supply voltage
was over the range of the
inverter's specifications.
(2) The acceleration time was
too short.
(3) The deceleration time
was too short for the
moment of inertia for load.
(4) Loads were suddenly
removed.
(5) Braking load was too
heavy.
(6) Malfunction caused by
noise.
LU
[ 3 ] Undervoltage protection
Problem DC link circuit voltage was below the undervoltage detection level.
Possible Causes
(1) An instantaneous power
failure occurred.
Overvoltage occurs during the acceleration.
Overvoltage occurs during the deceleration.
Overvoltage occurs during running at constant speed.
What to Check and Suggested Measures
Measure the input voltage.
Decrease the voltage to within that of the specifications.
Check if the overvoltage alarm occurs after sudden
acceleration.
Increase the acceleration time (F07, E10, and H54).
Select the S-curve pattern (H07).
Consider the use of a braking resistor.
Recalculate the deceleration torque from the moment of
inertia for load and the deceleration time.
Increase the deceleration time (F08, E11, and H54).
Enable automatic deceleration (H69=1) so that when the
DC link
suppression level, the inverter changes the deceleration
time to three times longer than the set value.
Set the rated voltage (at base frequency) (F05) to 0 to
improve braking ability.
Consider the use of a braking resistor.
- Check if the alarm occurs when loads are suddenly
removed.
- Check if the inverter operation suddenly changes from
driving operation to braking operation.
Consider the use of a braking resistor.
Compare the braking torque of the load with that of the
inverter.
Set the rated voltage (at base frequency) (F05) to 0 to
improve braking ability.
Consider the use of a braking resistor.
Check if the DC link circuit voltage was below the protective
level when the alarm occurred.
Improve noise control.
Enable the auto-reset function (H04).
What to Check and Suggested Measures
Reset the alarm.
If you want to restart running the motor without making the
alarm occur, set 4 or 5 to F14 depending on load.
circuit voltage
6-10
exceeds the overvoltage