Danfoss VLT AutomationDrive FC 302 Instruction Manual page 133

Warnings and Alarms
WARNING/ALARM 8, DC undervoltage
If the DC link voltage drops below the undervoltage limit,
the adjustable frequency drive checks if a 24 V DC backup
supply is connected. If no 24 V DC backup supply is
connected, the adjustable frequency drive trips after a
fixed time delay. The time delay varies with unit size.
Troubleshooting
Make sure that the supply voltage matches the
adjustable frequency drive voltage.
Perform input voltage test.
Perform soft charge circuit test.
WARNING/ALARM 9, Inverter overload
The adjustable frequency drive is about to cut out because
of an overload (current too high for too long). The counter
for electronic, thermal inverter protection issues a warning
at 98% and trips at 100%, while giving an alarm. The
adjustable frequency drive cannot be reset until the
counter is below 90%.
The fault is that the adjustable frequency drive has run
with more than 100% overload for too long.
Troubleshooting
Compare the output current shown on the LCP
with the adjustable frequency drive 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
adjustable frequency drive continuous current
rating, the counter increases. When running
below the adjustable frequency drive 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 adjustable frequency
drive 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.
MG37A222
Instruction Manual
Troubleshooting
WARNING/ALARM 11, Motor thermistor over-temp
The thermistor may be disconnected. Select whether the
adjustable frequency drive issues a warning or an alarm in
1-90 Motor Thermal Protection.
Troubleshooting
Danfoss A/S © Rev. 2014-02-07 All rights reserved.
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 to
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 adjustable frequency drive to the
motor more accurately and reduces thermal
loading.
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). Also check
that the terminal switch for 53 or 54 is set for
voltage. Check that 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.
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.
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