Fault
code
Fault descriptions
Possible reasons
Troubleshooting
Improper V/F curve or torque boost
settings
Adjust the V/F curve and torque
boost amount
The grid voltage is too low
Check grid voltage
The motor is blocked or the load
suddenly changes too much
Check the load
Motor overload protection factor
setting is incorrect
Correctly set the motor overload
protection factor
Improper V/F curve or torque boost
settings
Adjust the V/F curve and torque
boost amount
The grid voltage is too low
Check grid voltage
The motor is blocked or the load
suddenly changes too much
Check the load
Motor overload protection factor
setting is incorrect
Correctly set the motor overload
protection factor
BIAS(17)
Current bias error
Hardware malfunction
Contact suppliers for service
VFD power is too small
Select a higher power drive
Sudden change or abnormal of
load
Check the load or reduce the
change of the load
Loose PID feedback line
Check feedback connection
The feedback amount is less than
the disconnection detection value
Adjust the detection input
threshold
Check feedback connection
Adjust the detection input
threshold
EEEP(21)
EPROM read and write
errors
EEPROM malfunction
Contact suppliers for service
CE(22
）
Dual CPU
communication
malfunction
CPU communication malfunction
Contact suppliers for service
EF(23)
External device
malfunction
External device fault input terminal
is closed
Disconnect the external device
fault input terminal and clear the
fault (pay attention to check the
cause)
EPA(24
)
Parameter setting error
SFOC(27)
Software overcurrent
Adjust the acceleration time,
deceleration time, motor
parameters do not match, re-
parameter identification
ELT
Water shortage
malfunction
EPA1
parameter setting error
VFD three-wire function setting is
incorrect
Check whether the three-wire
system setting of the inverter
terminals is correct
OL1(15)
VFD overload
OL2(16)
Motor overload
CBC(18)
Cycle-by-cycle current
limit malfunction
FBL(19)
PID feedback is lower
than the lower limit
FBH(20)
PID feedback exceeds
upper limit
Warning code
When the PID feedback amount is
greater than the feedback over-
value detection value, and the
duration exceeds the PID feedback
over-value detection time, the
inverter will alarm fault FBH
22
E
485
(2
5
)
Communication
error
