Danfoss VLT Series Programming Manual page 201

Troubleshooting
WARNING/ALARM 2, Live zero error
This warning or alarm will only appear if programmed by
the user in 6-01 Live Zero Timeout Function. The signal on
one of the analog inputs is less than 50% of the minimum
value programmed for that input. This condition can be
caused by broken wiring or faulty device sending the
signal.
Troubleshooting
4 4
Check connections on all the analog input
terminals. Control card terminals 53 and 54 for
signals, terminal 55 common. MCB 101 terminals
11 and 12 for signals, terminal 10 common. MCB
109 terminals 1, 3, 5 for signals, terminals 2, 4, 6
common).
Check that the frequency converter programming
and switch settings match the analog signal type.
Perform Input Terminal Signal Test.
WARNING/ALARM 4, Mains phase loss
A phase is missing on the supply side, or the mains
voltage imbalance is too high. This message also appears
for a fault in the input rectifier on the frequency converter.
Options are programmed at 14-12 Function at Mains
Imbalance.
Troubleshooting: Check the supply voltage and supply
currents to the frequency converter.
WARNING 5, DC link voltage high
The intermediate circuit voltage (DC) is higher than the
high voltage warning limit. The limit is dependent on the
frequency converter voltage rating. The unit is still active.
WARNING 6, DC link voltage low
The intermediate circuit voltage (DC) is lower than the low
voltage warning limit. The limit is dependent on the
frequency converter voltage rating. The unit is still active.
WARNING/ALARM 7, DC overvoltage
If the intermediate circuit voltage exceeds the limit, the
frequency converter trips after a time.
Troubleshooting
Connect a brake resistor
Extend the ramp time
Change the ramp type
Activate the functions in 2-10 Brake Function
Increase 14-26 Trip Delay at Inverter Fault
WARNING/ALARM 8, DC under voltage
If the intermediate circuit voltage (DC link) drops below
the under voltage limit, the frequency converter checks if a
24V DC backup supply is connected. If no 24V DC backup
supply is connected, the frequency converter trips after a
fixed time delay. The time delay varies with unit size.
200
®
VLT HVAC Drive Programming Guide
Troubleshooting:
WARNING/ALARM 9, Inverter overload
The frequency converter is about to cut out because of an
overload (too high current for too long). The counter for
electronic, thermal inverter protection gives a warning at
98% and trips at 100%, while giving an alarm. The
frequency converter cannot be reset until the counter is
below 90%.
The fault is that the frequency converter is overloaded by
more than 100% for too long.
Troubleshooting
See the derating section in the Design Guide for more
details if a high switching frequency is required.
WARNING/ALARM 10, Motor overload temperature
According to the electronic thermal protection (ETR), the
motor is too hot. Select whether the frequency converter
gives a warning or an alarm when the counter reaches
100% in 1-90 Motor Thermal Protection. The fault occurs
when the motor is overloaded by more than 100% for too
long.
Troubleshooting
WARNING/ALARM 11, Motor thermistor over temp
The thermistor might be disconnected. Select whether the
frequency converter gives a warning or an alarm in
1-90 Motor Thermal Protection.
®
MG.11.CC.02 - VLT is a registered Danfoss trademark
Check that the supply voltage matches the
frequency converter voltage.
Perform input voltage test
Perform soft charge circuit test
Compare the output current shown on the LCP
with the frequency converter rated current.
Compare the output current shown on the LCP
with measured motor current.
Display the Thermal Drive Load on the LCP and
monitor the value. When running above the
frequency converter continuous current rating,
the counter should increase. When running below
the frequency converter continuous current
rating, the counter should decrease.
Check for motor overheating.
Check if the motor is mechanically overloaded
Check that the motor current set in 1-24 Motor
Current is correct.
Ensure that Motor data in parameters 1-20
through 1-25 are set correctly.
If an external fan is in use, check in 1-91 Motor
External Fan that it is selected.
Running AMA in 1-29 Automatic Motor Adaptation
(AMA) may tune the frequency converter to the
motor more accurately and reduce thermal
loading.