Cause Remedy
Over voltage
Decel time is too short compared to the
GD
2
of the load.
Regenerative load is connected at the
inverter output.
Line voltage is too high.
Use Dynamic Brake Unit.
Check whether line voltage exceeds
Load larger than line capacity is
connected to line (ex: welding machine,
motor with high starting current
connected to the commercial line).
Faulty magnetic switch at the input side
Check whether line voltage is below
its rating.
Check the incoming AC line. Adjust
the line capacity corresponding to the
load.
Change a magnetic switch.
Load is greater than inverter rating.
ETH level is set too low.
Inverter capacity is incorrectly selected.
Inverter has been operated at low speed
for too long.
Reduce load capacity and operating
duty.
Change inverter with higher capacity.
Adjust ETH level to an appropriate
level.
Select correct inverter capacity.
Install a cooling fan with a separate
The terminal set to “18 (External fault-
A)” or “19 (External fault-B)” in I20-I24 in
I/O group is ON.
Eliminate the cause of fault at circuit
connected to external fault terminal or
cause of external fault input.
External fault
Operating
method when
the frequency
command is
No frequency command is applied to V1
Check the wiring of V1 and I and
frequency reference level.
Remote
keypad
communication
Communication error between inverter
keypad and remote keypad
communication line and connector.
Brake control
No brake open current is flowing.
Check the Motor Capacity & Wiring.