Danfoss VLT AutomationDrive FC 300 Operating Instructions Manual page 65

Warnings and Alarms
The fault is that the frequency converter has run with
more than 100% overload for too long.
Troubleshooting
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 increases. When running below the
frequency converter continuous current rating,
the counter decreases.
WARNING/ALARM 10, Motor overload temperature
According to the electronic thermal protection (ETR), the
motor is too hot. Select whether the frequency converter
issues a warning or an alarm when the counter reaches
100% in 1-90 Motor Thermal Protection. The fault occurs
when the motor runs with more than 100% overload for
too long.
Troubleshooting
Check for motor overheating.
8 8
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) tunes the frequency converter to the
motor more accurately and reduces thermal
loading.
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.
Troubleshooting
Check for motor overheating.
Check if the motor is mechanically overloaded.
Check that the thermistor is connected correctly
between either terminal 53 or 54 (analog voltage
input) and terminal 50 (+10 V supply) and that
the terminal switch for 53 or 54 is set for voltage.
Check 1-93 Thermistor Source selects terminal 53
or 54.
When using digital inputs 18 or 19, check that
the thermistor is connected correctly between
either terminal 18 or 19 (digital input PNP only)
and terminal 50.
62
®
VLT Automation Drive D-Frame
Operating Instructions
WARNING/ALARM 12, Torque limit
The torque has exceeded the value in 4-16 Torque Limit
Motor Mode or the value in 4-17 Torque Limit Generator
Mode. 14-25 Trip Delay at Torque Limit can change this from
a warning only condition to a warning followed by an
alarm.
Troubleshooting
WARNING/ALARM 13, Over current
The inverter peak current limit (approximately 200% of the
rated current) is exceeded. The warning lasts about 1.5 s,
then the frequency converter trips and issues an alarm.
This fault may be caused by shock loading or quick
acceleration with high inertia loads. It may also appear
after kinetic back-up if the acceleration during ramp up is
quick. If extended mechanical brake control is selected, trip
can be reset externally.
Troubleshooting
ALARM 14, Earth (ground) fault
There is current from the output phases to earth, either in
the cable between the frequency converter and the motor
or in the motor itself.
Troubleshooting:
®
MG34U202 - VLT is a registered Danfoss trademark
If a KTY sensor is used, check for correct
connection between terminals 54 and 55
If using a thermal switch or thermistor, check that
the programming if 1-93 Thermistor Resource
matches sensor wiring.
If using a KTY sensor, check the programming of
1-95 KTY Sensor Type, 1-96 KTY Thermistor
Resource, and 1-97 KTY Threshold level match
sensor wiring.
If the motor torque limit is exceeded during ramp
up, extend the ramp up time.
If the generator torque limit is exceeded during
ramp down, extend the ramp down time.
If torque limit occurs while running, possibly
increase the torque limit. Be sure the system can
operate safely at a higher torque.
Check the application for excessive current draw
on the motor.
Remove power and check if the motor shaft can
be turned.
Check that the motor size matches the frequency
converter.
Check parameters 1-20 to 1-25 for correct motor
data.
Remove power to the frequency converter and
repair the earth fault.
Check for earth faults in the motor by measuring
the resistance to ground of the motor leads and
the motor with a megohmmeter.