E.SPO
Output side phase
loss
Output UVW has phase loss
Check output wiring
error code
Fault type
Possible cause of failure
Countermeasures
E.OV2
Inverter
deceleration
running over
voltage
1. Motor short circuit to ground
Check motor connection
2. Potential energy load or load inertia
torque is large
plus suitable dynamic braking
components
3. The deceleration time is too short Extend deceleration time
E.OV3
Inverter
running at
constant speed
overvoltage
1. Motor short circuit to ground
Check motor connection
2. During vector control, the ASR parameter
setting is improper
Set appropriate ASR parameters
3. The acceleration and deceleration time
setting is too short
Appropriately extend the acceleration
and deceleration time
4. Abnormal input voltage
Check input power
5. The input voltage fluctuates abnormally
Install input reactor
6. Large load inertia
plus suitable dynamic braking
components
E.SPI
Input side phase
loss
Input RST has phase loss
Check installation wiring
Check input voltage
Check the motor and cables
E.FO
Power Module
Protection
1. The three output phases have phase - to-
phase short circuit or ground short circuit
Re-wiring, confirm whether the
insulation of the motor is good
2. Instantaneous overcurrent of the inverter
See Overcurrent Countermeasures
3. The air duct is blocked or the fan is
damaged
Unclog the duct or replace the fan
4. The ambient temperature is too high
reduce ambient temperature
5. The control board connection or plug-in
is loose
Check and reconnect
6. The current waveform is abnormal due to
the lack of output phase
Check wiring
7. The auxiliary power supply is damaged,
and the driving voltage is undervoltage
seek service
8. Inverter module bridge arm straight
through
seek service
9. The control panel is abnormal
seek service
E.OH1
radiator
overheating
1. The ambient temperature is too high
reduce ambient temperature
2. Duct blockage
Clean up the air duct
3. The fan is broken
replace the fan
4. The inverter module is abnormal seek service
5. Temperature check circuit failure
seek service
E.OH2
rectifier bridge
overheating
1. The ambient temperature is too high
reduce ambient temperature
2. Duct blockage
Clean up the air duct
3. The fan is broken
replace the fan
4. Temperature check circuit failure
seek service
E.OL2
Inverter overload
1. Motor parameters are inaccurate
Carry out motor parameter auto-
tuning again
2. Excessive load
Choose a higher power inverter
3. The amount of DC braking is too large
Reduce the DC braking current and
prolong the braking time
4. Acceleration time is too short Extend acceleration time
5. Grid voltage is too low Check grid voltage
6. The V/F curve is not suitable
Correctly set the V/F curve and torque
boost
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NVF2G-S Series Inverter User's Guide