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Chapter 7 Fault Diagnosis
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Chapter 7 Fault Diagnosis
7.1 List of Fault and Alarm Information
V5
−
H serial inverter is equipped with complete protection functions to provide efficient protection while
utilizing its performance sufficiently. Some failure instructions may be displayed during operation.
Compare the instructions with the following table and analyze, decide the causes and solve failures.
For damages on units or questions that can’t be resolved, please contact with local distributors/agents,
service centers or manufacturer for solutions.
Failure No.
Failure code
Failure description
Potential causes
Solutions
1
E.oc1
Over current
protection when
acceleration
operation
Low grid voltage
Check input power supply
Startup too fast during
motor operation
Restart after the motor stops
rotating
Rotating inertial of load is
very large and shock load
is very heavy
Increase the acceleration time
and reduce the occurrences of
sudden change of load
Improper setting of motor
parameters
Set motor parameters properly
Set start-up frequency too
high
Decrease start-up frequency
Acceleration time is too
short
Lengthen acceleration time
Set V/F curve ratio too large
Adjust V/F curve setting and
torque boost
Power level of inverter is
small
Replace with inverter with
proper model
2
E.oc2
Over current
protection when
deceleration
operation
Low grid voltage
Check input power supply
Rotating inertial of load is
too large
Choose appropriate energy
braking components
Improper setting of motor
parameters
Set motor parameters properly
Deceleration time is too
short
Lengthen deceleration time
Power level of inverter is
small
Replace to inverter with proper
model
3
E.oc3
Over current
protection when
operation with
constant speed
Sudden change of load
during operation
Decrease load’s abrupt
frequency change and
amplitude
Improper setting of motor
parameters
Set motor parameters properly
Power level of inverter is
small
Replace to inverter with proper
model
4
E.oV1
Over voltage
protection when
acceleration
operation
Motor short to ground
Check motor wiring
Abnormal input power
supply voltage
Check input power supply
Fast start-up again when
motor operates with high
speed
Start again after the motor stop
rotating
5
E.oV2
Over voltage
protection when
deceleration
operation
Motor short to ground
Check motor wiring
Rotating inertial of load is
too large
Choose appropriate energy
braking components
Deceleration time is too
short
Lengthen deceleration time
