Instruction manual

8. Fault Diagnosis
167
Fault Display
Fault Displays and Meanings
Fault Display Inverter
Status
Description Causes and Corrective
Actions
Digital
Operator
RUN (Green)
ALARM (Red)
Protective
Operation
Output is
turned OFF
and motor
coasts to a
stop.
OC (Overcurrent)
Inverter output current mo-
mentarily exceeded approx.
250% of rated current.
Operation is restored, if no
fault is found, after confirming
the following:
• Short circuit or grounding
at Inverter output side
• Excessive load GD
2
• Extremely rapid
Acceleration/Deceleration
Time (constants n019 to
n022)
• Special motor used
• Starting motor during
coasting
• Motor of a capacity
greater than the Inverter
rating has been started.
• Magnetic contactor
opened/closed at the
Inverter output side
• Leak current increased
because of excessive
long wiring
GF (Grounding) *
Grounding current exceeded
approx. 50%
of Inverter rated output cur-
rent at the Inverter output
side.
Inverter output grounded.
⇓
Check the cause, and re-
store the operation.
SC (Load shortcircuit) *
Inverter output or load short-
circuited.
Inverter output shortcircuited
or grounded.
⇓
Check the cause, and re-
store the operation.
OV (Main circuit over-
voltage)
Main circuit DC voltage level
exceeded the overvoltage de-
tection level while the Inverter
was running.
Detection level (DC voltage:
Voltage between terminals
"+1" and "-")
200 V: Approx. 410 V or more
400 V: Approx. 820 V or more
1. Regenerative energy is
large.
• The setting of decelera-
tion time is too short.
• Negative load (e.g., ele-
vator) is excessive at
lowering.
• Confirm that the load
does not have any prob-
lem.
2. Input voltage is errone-
ous.
Confirm that DC voltage
exceeding the left value
is not input.
* Indicates that an Inverter of 5.5 kW and 7.5 kW (200-V and 400-V classes) is attached.