YASKAWA Varispeed V7 Series, Quick Start Manual

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33
8. Faults and alarms
Note: Refer to user’s manual for full fault code listings
Fault
Display
Fault name and meaning Possible cause and remedy
OC Overcurrent
Output current is higher than
250% of inverter rated current.
Check output for shortcircuit or ground fault.
The load is too large, reduce it or use larger
inverter. Check motor FLA rating compared to
inverter and V/f setting.
OV Overvoltage
DC bus voltage has exceeded
detection level.
Load inertia is too large and the motor is re-
generating. Increase deceleration time (n020
or n022).
Connect an external braking resistor and set
n092 to 1. Check braking resistor and wiring.
UV1 Main circuit undervoltage
DC bus voltage is below detec-
tion level.
Check mains power supply voltage and con-
nections. Check correct supply for inverter
beeing used.
Monitor for mains dips or interruptions.
OH Unit overheat
Temperature inside the inverter
has exceeded 110°C
Refer to manual for installation guidelines
and recommendations. Check cooling fan (if
fitted). Check v/f characteristic or reduce car-
rier frequency.
OL1 Motor overload
The inverter is protecting the
motor from overload, based on
an internal I
2
t calculation using
n036 setting.
Check and reduce the load.
Check V/f characteristic (Vmax and Fmax).
Increase the running speed of motor.
Increas acceleration/deceleration times.
EF External fault
An external fault has been input.
Check your control terminal wiring.
A multi-function digital input has been set to 3
or 4. Run signal has to be removed before
this can be reset.
SER
(flashing)
Sequence error
Sequence input when inverter is
running.
Inverter has to be stopped when Local /
Remote switching attempted.
Inverter must be stopped when Comms /
Remote switching attempted.
bb
(flashing)
External Baseblock
An external baseblock com-
mand has been input.
Check your control terminal wiring.
A multi-function digital input has been set to
12 or 13.
EF
(flashing)
Sequence error has occurred Forward and reverse run signal have been
applied simultaniously.