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95
16. Troubleshooting table ■
Description of alarm display indications
Error
indication
Description of fault operation
Item for inspection
Processing
Err Operation
error
Was the unit operated as
indicated in the manual
Use the correct procedure
ErO
Operation error of internal ROM,
RAM
Switch off the power and then
apply again
Replace the unit
ErC
Error of internal CPU
Is there a large amount of
external noise
Check the contact absorber.
Install a noise filter
OCPA
Over current (180% rated
current)
Was there rapid acceleration
Lengthen the acceleration
time
OCPd
Over current (180% rated
current)
Was there rapid deceleration
Lengthen the deceleration
time
OCPn
Over current (180% rated
current)
Was there any variation in the
load
Lengthen the time for the
load variations
OC
Over current (200% rated
current)
Was there rapid acceleration /
deceleration and variation in the
load
Lengthen the acceleration
and deceleration time and
reduce the load
OCS
Output short circuit or ground
detected
Is there a short circuit for the
output or grounding for the
motor
Perform a megger check for
the motor
OU
DC link over voltage
Was there fast deceleration, or
fast voltage
Lengthen the deceleration
time. Investigate the use of
the optional DBR
LU
Insufficient voltage detected due
to power failure or instantaneous
power loss.
Is there a low voltage at power,
or internal inverter wiring error
Improve the voltage
condition and confirm
inverter model
LU A
Insufficient voltage detected due
to power failure or instantaneous
power loss. And the auto save
function is working
Is there a low voltage at power,
or internal inverter wiring error
Improve the voltage
condition and confirm
inverter model
LU b
Insufficient voltage detected due
to power failure or instantaneous
power loss. And the auto save
function is working
Is there a low voltage at power,
or internal inverter wiring error
Improve the voltage
condition and confirm
inverter model
OH
Overheating of the cooling fan
detected
1.
Cooling fan stops
2.
Ambient temperature too
hot
3.
Motor being overload
1.
Exchange the cooling
fan
2.
Lower the ambient
temperature
3.
Check the load
conditions
OL
Overload detected for more than
one minute
Is the motor being overloaded
Increase the capacity of the
inverter and motor
OL b
Over load alarm for more than
one minute
Is the motor being overloaded
Increase the capacity of the
inverter and motor
PLU
Power voltage too low
Is power voltage too low
Improve power supply
condition
Fb
Fuse blown
Is the fuse blown
Change a fuse