1-7
Fault Display and Troubleshooting
If a fault occurs and the inverter functions are lit, check for the
causes and provide proper corrective actions, referring to the fol-
lowing checking method.
1-7-1 Checking of Causes
The inverter has protective functions to protect it from faults such
as overcurrent or overvoltage. If a fault occurs, the protective func-
tions operate to shut off the inverter output and the motor coasts to
a stop. At the same time, the fault contact signal is output.
When the protective functions operate, the digital display unit dis-
plays the fault shown in Table 5. Also when the digital operator is
used, the same display except for control function faults is pro-
vided. (Refer to note 1 following Table 5.)
Operation can be restarted by turning on the reset input signal or
turning off the power supply once.
Table 5 Fault Display and Contents
Fault display
Contents
Possible cause/corrective actions
OC (Overcurrent)
Inverter output current exceeds
200% of rated current.
(Momentary action)
The following causes can be considered: in-
verter output side short-circuit, excessive
load GD
2
, excessively short setting of accel/
decel time, special motor use, motor start
during coasting, start of motor with larger ca-
pacity than inverter, inverter output side mag-
netic contactor on/off.
Reset after finding the cause.
GF (Ground Fault)
Inverter output side is
grounded.
Check that the motor or load side wiring is
not grounded.
OV (Overvoltage)
Main circuit DC voltage ex-
ceeds 410 V or more because
of excessive regenerative ener-
gy from motor.
Decel time setting is not sufficient or minus
load (elevators, etc.) is decreasing.
Increase decel time or connect a braking re-
sistor (option).
UV (Undervoltage)
Undervoltage status is entered.
(or main circuit DC voltage be-
comes 210 V or less, or less
than undervoltage detection
level.)
Input power supply voltage is reduced,
phases are opened or momentary power loss
occurs, etc.
Check the power supply voltage, or check
that main circuit power supply wiring is con-
nected properly or terminal screws are tight-
ened well.
OH (Inverter Overheat)
Thermistor operates because of
inverter overload operation or
ambient temperature rise.
Load is too large, V/f characteristics are not
proper, setting time is too short or ambient
temperature exceeds 45
C, etc. Correct
load size, V/f set value or ambient tempera-
ture.
(No display)
(Fuse Blown)
Main circuit fuse is blown.
Replace the inverter.
OL1 (Motor Overload)
Motor overload protection oper-
ates because of electronic over-
load thermal.
Correct load size, operation pattern or V/f set
value. Set the rated current value described
in the motor nameplate.
Section 1-7
Summary of Contents for SYSDRIVE 3G3SV
Page 1: ...6 6 5 9 69 19 57 5 69 BB 69 BB 2SHUDWLRQ 0DQXDO...
Page 3: ...0 1 2 3...
Page 5: ...2 4 4 3 4 5 5 6 7 8 8...
