7
-4
OL3
Overtorque Det 1
F/A
Overtorque Detected 1
(Operation selection – L6-01)
There has been a current greater than the set-
ting in L6-02 for longer than the setting in
L6-03.
• Make sure that the settings in L6-02 and
L6-03 are appropriate.
• Check the mechanical system and correct
the cause of the overtorque.
OL4
Overtorque Det 2
F/A
Overtorque Detected 2
(Operation selection – L6-04)
There has been a current greater than the set-
ting in L6-05 for longer than the setting in
L6-06.
• Make sure that the current setting in L6-
05 and time setting in L6-06 are appropri-
ate.
• Check the mechanical system and correct
the cause of the overtorque.
UL3
Undertorque Det 1
F/A
Undertorque Detected 1
(Operation selection – L6-01)
There has been a current less than the setting
in L6-02 for longer than the setting in L6-03.
• Make sure that the settings in L6-02 and
L6-03 are appropriate.
• Check the mechanical system and correct
the cause of the overtorque.
UL4
Undertorque Det 2
F/A
Undertorque Detected 2
(Operation selection – L6-04)
There has been a current less than the setting
in L6-05 for longer than the setting in L6-06.
• Make sure that the current setting in L6-
05 and time setting in L6-06 are appropri-
ate.
• Check the mechanical system and correct
the cause of the overtorque.
PGO
PG Open
F/A
PG Disconnection Detected
(Operation selection – H7-02)
PG pulses were input when the Inverter was
outputting a frequency.
• Fix the wiring.
• Supply power to the PG properly.
• Check the PG itself (output).
DEV
Speed Deviation
F/A
Excessive Speed Deviation
(Operation selection – H7-04)
The speed deviation has been greater than the
setting in H7-10 for longer than the setting in
H7-11.
• Reduce the load.
• Lengthen the acceleration time and decel-
eration time.
Constant: C1-
• Check the settings in H7-10 and H7-11.
OS
Overspeed Det
F
Overspeed
The speed has been greater than the setting in
H7-08 for longer than the setting in H7-09.
• Check the settings in H7-08 and H7-09.
• Make sure that the motor constants are
appropriate.
Constant: E-
, E2-
• Check the mechanical system and correct
the cause of the overtorque.
OGF
Ground Fault
F
Output Ground Fault
The ground fault current at the Inverter out-
put exceeded approximately 25% of the
Inverter rated output current.
Or, the zero-phase voltage at the Inverter out-
put exceeded the ground fault detection level
(L9-21) for the detection time (L9-22).
• Measure motor and cable insulation resis-
tances.
• Check the motor cable.
LF
Output Pha Loss
F
Output Open-phase
An open-phase occurred at the Inverter out-
put.
This fault is detected when L8-07 is set to
“Enabled.”
• Check the motor cable.
EF
External Fault
A
Forward/Reverse run Simultaneous Input
The forward-run and the reverse–run input
continued 0.3 seconds or more simulta-
neously.
• Check the input sequence.
Note When this alarm is occurred, a motor is slowed
down and stops.
Table 7.1 List of Drive Faults (Continued)
Fault Display
Rank
Fault Details
Corrective Actions
