Danfoss FC 300 Operating Instruction Download

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FC 300 Operating Instructions

Warnings and Alarms

WARNING 6
DC link voltage low

The intermediate circuit voltage (DC) is below
the undervoltage limit of the control system. The
frequency converter is still active.

WARNING/ALARM 7
DC over voltage:

If the intermediate circuit voltage exceeds the limit,
the frequency converter 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

3 x 380 -
500 V

3 x 525 -

600 V

[VDC]

Undervoltage

185

373

532

Voltage
warning low

205

410

585

Voltage
warning high
(w/o brake -
w/brake)

390/405

810/840

943/965

Overvoltage

410

855

975

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 frequency converter checks if 24
V backup supply is connected.
If no 24 V backup supply is connected, the
frequency converter trips after a given time
depending on the unit.
To check whether the supply voltage matches the
frequency converter, see

General Specifications

WARNING/ALARM 9
Inverter overloaded:

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. You cannot reset the frequency
converter until the counter is below 90%.
The fault is that the frequency converter 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. You can choose if you
want the frequency converter to give 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. You can choose if you want the
frequency converter to give 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 frequency
converter trips and issues an alarm. Turn
off the frequency converter and check if the
motor shaft can be turned and if the motor size
matches the frequency converter.
If extended mechanical brake control is selected,
trip can be reset externally.

ALARM 14
Earth fault:

There is a discharge from the output phases to
earth, either in the cable between the frequency
converter and the motor or in the motor itself.
Turn off the frequency converter and remove
the earth fault.

MG.33.A7.02 - VLT is a registered Danfoss trademark