0U2 Overvoltage - Fuji Electric FRN0001C2S-2A FRN0002C2S-2A FRN0004C2S-2A FRN0006C2S-2A FRN0010C2S-2A FRN0012C2S-2A FRN0020C2S-2A FRN0025C2S-2A FRN0033C2S-2A FR Instruction Manual

Possible Causes
(3) Loads were too heavy.
(4) Excessive torque boost
specified.
(when F37, A13 = 0, 1, 3
or 4)
(5) Acceleration/
deceleration time
currently specified is too
short.
(6) Malfunction caused by
noise.
[ 2 ] n Overvoltage
0u
Problem The DC link bus voltage was over the detection level of overvoltage.
0u1
0u2
0u3
Possible Causes
(1) The power supply
voltage exceeded the
inverter's specification
range.
(2) A surge current entered
the input power supply.
What to Check and Suggested Measures
Measure the motor current with a measuring device to trace the
current trend. Then, use this data to judge if the trend is over the
calculated load value for your system design.
If the load is too heavy, reduce it or raise the inverter capacity.
Trace the current trend and check if there are any sudden changes
in the current.
 If there are any sudden changes, make the load fluctuation
smaller or raise the inverter capacity.
 Enable instantaneous overcurrent limiting (H12 = 1).
Check whether decreasing the torque boost (F09, A05) reduces the
output current but does not stall the motor.
 If no stall occurs, decrease the torque boost (F09, A05).
Recalculate the acceleration/deceleration torque and time needed
for the current load, based on the moment of inertia of the load and
the acceleration/deceleration time.
 Increase the acceleration/deceleration time (F07, F08, E10,
E11).
 Enable current limiter (F43)
 Raise the inverter capacity.
Check if noise control measures are appropriate (e.g., correct
grounding and routing of control and main circuit wires).
 Implement noise control measures. For details, refer to the
FRENIC-Mini User's Manual, "Appendix A."
 Enable the Auto-reset (H04).
 Connect a surge absorber to magnetic contactor's coils or other
solenoids (if any) causing noise.
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 the specified range.
In the same power line, if a phase-advancing capacitor is turned
ON/OFF or a thyristor converter is activated, a surge (momentary
large increase in the voltage or current) may be caused in the input
power.
 Install a DC reactor.
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