10-2
LED display
Description
Cause
Possible solutions
O
ver
C
urrent
The inverter output current
exceeds the overcurrent level
during deceleration
Deceleration time is set too short
Set longer acceleration
time
Ground Fault
The ground fault exceeds
50% of the inverter rated
output current (08-23 = 1, GF
function is enabled).
Motor damaged (insulation).
Wire damage or deterioration.
Inverter DCCT sensors defect.
Replace motor.
Check motor wiring.
Disconnect motor and try
running inverter.
Check resistance between
cables and ground.
Reduce carrier frequency.
Over voltage
DC bus voltage exceeds the
OV detection level:
200V class: 410Vdc
400V class: 820Vdc
Deceleration time set too short,
resulting in regenerative energy
flowing back from motor to the
inverter.
The inverter input voltage is too high.
Use of power factor correction
capacitors.
Excessive braking load.
Braking transistor or resistor
defective.
Speed search parameters set
incorrectly.
Increase deceleration time
Reduce input voltage to
comply with the input
voltage requirements or
install an AC line reactor to
lower the input voltage.
Remove the power factor
correction capacitor.
Use dynamic braking unit.
Replace braking transistor
or resistor.
Adjust speed search
parameters.
Under Voltage
DC bus voltage is lower than
the UV detection level or the
pre-charge contactor is not
active while the inverter is
running.
200V class: 190Vdc
400V class: 380Vdc
The detection value
can be adjusted by
07-13).
The input voltage is too low.
Input phase loss.
Acceleration time set too short.
Input voltage fluctuation.
Pre-charge contactor damaged.
DC bus voltage feedback signal
value not incorrect.
Check the input voltage.
Check input wiring.
Increase acceleration time.
Check power source
Replace pre-charge
contactor
Replace control board or
complete inverter.