Danfoss VLT AutomationDrive FC 300 Design Manual page 266

FC 300 Design Guide
WARNING/ALARM 7
DC over voltage:
If the intermediate circuit voltage exceeds the limit,
the adjustable frequency drive trips after a time.
Possible corrections:
Connect a brake resistor
Extend the ramp time
Activate functions in par. 2-10
Increase par. 14-26
Connect a brake resistor. Extend the ramp time
Alarm/warning limits:
FC 300 Series 3 x 200 -
240 V
[VDC]
Undervoltage 185
Voltage 205
warning low
Voltage 390/405
warning high
(w/o brake -
w/brake)
Overvoltage 410
The voltages stated are the intermediate circuit
voltage of the FC 300 with a tolerance of ± 5 %. The
corresponding mains voltage is the intermediate
circuit voltage (DC-link) divided by 1.35
WARNING/ALARM 8
DC under voltage:
If the intermediate circuit voltage (DC) drops
below the "voltage warning low" limit (see table
above), the adjustable frequency drive checks
if 24 V backup supply is connected.
If no 24 V backup supply is connected, the
adjustable frequency drive trips after a given
time depending on the unit.
To check whether the supply voltage
matches the adjustable frequency drive, see
General Specifications.
WARNING/ALARM 9
Inverter overloaded:
The adjustable frequency drive 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%
266
Troubleshooting
3 x 380 - 3 x 525 -
500 V 600 V
[VDC] [VDC]
373 532
410 585
810/840 943/965
855 975
MG.33.B3.22 - VLT is a registered Danfoss trademark
and trips at 100%, while giving an alarm. You
cannot reset the adjustable frequency drive
until the counter is below 90%.
The fault is that the adjustable frequency drive is
overloaded by more than 100% for too long.
WARNING/ALARM 10
Motor ETR over temperature:
According to the electronic thermal protection
(ETR), the motor is too hot. It is possible to select
whether the adjustable frequency drive provides
a warning or an alarm when the counter reaches
100% in par. 1-90. The fault is that the motor is
overloaded by more than 100% for too long. Check
that the motor par. 1-24 is set correctly.
WARNING/ALARM 11
Motor thermistor over temp:
The thermistor or the thermistor connection is
disconnected. Choose whether the adjustable
frequency drive should provide a warning or an
alarm when the counter reaches 100% in par. 1-90.
Check that the thermistor is connected correctly
between terminal 53 or 54 (analog voltage input)
and terminal 50 (+ 10 Volts supply), or between
terminal 18 or 19 (digital input PNP only) and
terminal 50. If a KTY sensor is used, check for
correct connection between terminal 54 and 55.
WARNING/ALARM 12
Torque limit:
The torque is higher than the value in par. 4-16 (in
motor operation) or the torque is higher than the
value in par. 4-17 (in regenerative operation).
WARNING/ALARM 13
Over Current:
The inverter peak current limit (approx. 200%
of the rated current) is exceeded. The warning
will last approx. 8-12 sec., then the adjustable
frequency drive trips and issues an alarm. Turn
off the adjustable frequency drive and check if the
crankshaft can be turned and if the motor size
matches the adjustable frequency drive.
If extended mechanical brake control is selected,
trip can be reset externally.
ALARM 14
Ground fault:
There is a discharge from the output phases to
ground, either in the cable between the adjustable
frequency drive and the motor or in the motor itself.