7 Troubleshooting
7-2
FVR-C11S-EN
7
2) Overvoltage(OU)
Overvoltage
during accelera-
tion OU1
Overvoltage
during decelera-
tion OU2
Overvoltage while
running at constant
speed OU3
z
Fix supply volt-
age to within up-
per limit of
specifications.
z
If caused by mo-
mentary voltage
surge from pow-
er supply, con-
sider installing a
power-factor
correcting DC
reactor.
Power supply voltage within specified value?
No
Yes
Yes
Yes
Does OU activate when load is removed suddenly.
Yes
z
Eliminate sud-
den change of
load.
z
Consider in-
creasing inverter
capacity.
No
No
No
Faulty inverter or
error because of
noise. Contact Fuji
Electric.
No
Main circuit DC voltage exceeds protection level?
Yes
Yes
Yes
No
Occurs on
completion of steep
acceleration?
Can decelerating
time be prolonged?
Prolong decelerat-
ing time.
Yes
No
Prolong accelerat-
ing time.
Yes
Can accelerating
time be prolonged?
No
Can the moment of inertia of load be
reduced?
Reduce moment
of inertia.
No
No
Can regenerating load be reduced?
Yes
Reduce regenerat-
ing load.
No
No
No
DC injection brake
used?
Consider using DC
injection brake.
Yes
Review braking method. Contact Fuji Electric.
Yes
Yes
No
