Envicool EMW90HDNC1A - Page 39

User Manual
7 Fault Management
EMW90HDNC1A Air-cooled Chiller
37
Alarm Name
Generation
Condition
Possible Causes
Processing Method
set value of low
pressure difference of
coolant pump.
The coolant circulating in
the chiller is mixed with
air, or there is no coolant,
resulting in idling of the
circulation pump.
Check the internal circulating
coolant.
Commun
Failure of
Freq
Converter
Communication failure
of compressor
frequency converter.
The upper computer
works abnormally.
Check the connecting line of the
upper computer.
Communication wiring of
frequency converter is
loose or cable is
damaged.
Fasten communication wiring or
replace cables.
Freq
Converter
Overcurrent
Compressor inverter
current is higher than
overcurrent alarm
point.
Inverter output circuit is
grounded or
short-circuited.
Troubleshoot the output circuit.
Low voltage.
Adjust the voltage to the normal
range.
Inverter selection is too
small.
Replace the inverter with higher
power level.
The motor is
short-circuited to ground.
Replace cables or motors.
The acceleration time is
too short, which leads to
acceleration overcurrent.
Increase the acceleration time.
Manual torque increase
or improper V/F curve
leads to acceleration
overcurrent.
Adjust the manual lifting torque
or V/F curve.
Starting the rotating motor
leads to accelerating
overcurrent.
Wait for the motor to stop
before starting.
Sudden loading during
acceleration/deceleration/
operation leads to
acceleration/deceleration/
constant speed
overcurrent.
Cancel the sudden load.
The deceleration time is
too short, resulting in
deceleration overcurrent.
Increase deceleration time.
Freq
Converter
OverTemp
Compressor
frequency converter
temperature is higher
than over-temperature
alarm point.
The cooling air duct of
compressor frequency
converter is blocked.
Clean the cooling air duct of
compressor frequency
converter.
The ambient temperature
is too high.
Lower the ambient temperature.
The fan is damaged.
Replace the frequency
converter.