10-2
LED display
Description
Cause
Possible solutions
OV
Over voltage
DC bus voltage exceeds
the OV detection level:
410Vdc: 230V class
820Vdc: 460V class
1050Vdc:575V class
1230Vdc:690V class
(For 440V class, if input
voltage 01-14 is set lower
than 400V, the OV
detection value will is
decreased to 700Vdc).
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.
UV
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.
190Vdc: 230V class;
380Vdc: 460V class
546Vdc:575/690V class
(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.
IPL input
phase loss
Phase loss at the input side
of the inverter or input
voltage imbalance, active
when 08-09 = 1 (enabled).
Wiring loose in inverter input
terminal.
Momentary power loss.
Input voltage imbalance.
Check input wiring / faster
screws.
Check power supply.
OPL output
phase loss
Phase loss at the output
side of the inverter, active
when 08-10 = 1 (enabled).
Wiring loose in inverter output
terminal.
Motor rated current is less than 10%
of the inverter rated current.
Check output wiring /
faster screws.
Check motor & inverter
rating.
OH1
Heatsink
overheat
The temperature of the
heat sink is too high.
Note: when OH1 fault
occurs three times within
five minutes, it is required
to wait 10 minutes before
resetting the fault.
Ambient temperature too high.
cooling fan failed
Carrier frequency set too high.
Load too heavy.
Install fan or AC to cool
surroundings.
Replace cooling fan.
Reduce carrier frequency.
Reduce load / Measure
output current
OL1
Motor
overload
Internal motor overload
protection tripped, active
when protection curve
08-05 = xxx1.
Voltage setting V/F mode too high,
resulting in over-excitation of the
motor.
Motor rated current (02-01) set
incorrectly.
Load too heavy.
Check V/f curve.
Check motor rated current
Check and reduce motor
load, check and operation
duty cycle.
