Danfoss VLT AutomationDrive FC 301, Руководство по эксплуатации, Страница: 45 / 84

For frequency converters with DC fans, there is a feedback
sensor mounted in the fan. If the fan is commanded to run
and there is no feedback from the sensor, this alarm
appears. For frequency converters with AC fans, the
voltage to the fan is monitored.
Troubleshooting
•
Check for proper fan operation.
•
Cycle power to the frequency converter and
check that the fan operates briefly at start-up.
•
Check the sensors on the heat sink and control
card.
WARNING 25, Brake resistor short circuit
The brake resistor is monitored during operation. If a short
circuit occurs, the brake function is disabled and the
warning appears. The frequency converter is still
operational, but without the brake function.
Troubleshooting
•
Remove the power to the frequency converter
and replace the brake resistor (see
parameter 2-15 Brake Check ).
WARNING/ALARM 26, Brake resistor power limit
The power transmitted to the brake resistor is calculated as
a mean value over the last 120 s of run time. The
calculation is based on the DC-link voltage and the brake
resistor value set in
parameter 2-16 AC brake Max. Current .
The warning is active when the dissipated braking power
is higher than 90% of the brake resistor power. If option
[2]
Trip is selected in parameter 2-13 Brake Power Monitoring ,
the frequency converter trips when the dissipated braking
power reaches 100%.
WARNING/ALARM 27, Brake chopper fault
The brake transistor is monitored during operation, and if a
short circuit occurs, the brake function is disabled, and a
warning is issued. The frequency converter is still
operational, but since the brake transistor has short-
circuited, substantial power is transmitted to the brake
resistor, even if it is inactive.
Troubleshooting
•
Remove power to the frequency converter and
remove the brake resistor.
WARNING/ALARM 28, Brake check failed
The brake resistor is not connected or not working.
Check
parameter 2-15 Brake Check .
ALARM 29, Heat Sink temp
The maximum temperature of the heat sink is exceeded.
The temperature fault is not reset until the temperature
drops below a defined heat sink temperature. The trip and
reset points are different based on the frequency converter
power size.
Troubleshooting
Check for the following conditions.
•
The ambient temperature is too high.
•
The motor cables are too long.
•
Incorrect airflow clearance above and below the
frequency converter.
•
Blocked airflow around the frequency converter.
•
Damaged heat sink fan.
•
Dirty heat sink.
ALARM 30, Motor phase U missing
Motor phase U between the frequency converter and the
motor is missing.
Troubleshooting
•
Remove the power from the frequency converter
and check motor phase U.
ALARM 31, Motor phase V missing
Motor phase V between the frequency converter and the
motor is missing.
Troubleshooting
•
Remove the power from the frequency converter
and check motor phase V.
ALARM 32, Motor phase W missing
Motor phase W between the frequency converter and the
motor is missing.
Troubleshooting
•
Remove the power from the frequency converter
and check motor phase W.
ALARM 33, Inrush fault
Too many power-ups have occurred within a short time
period.
Troubleshooting
•
Let the unit cool to operating temperature.
WARNING/ALARM 34, Fieldbus communication fault
The fieldbus on the communication option card is not
working.
WARNING/ALARM 35, Option fault
An option alarm is received. The alarm is option-specific.
The most likely cause is a power-up or a communication
fault.
WARNING/ALARM 36, Mains failure
This warning/alarm is only active if the supply voltage to
the frequency converter is lost and
parameter 14-10 Mains
Failure is not set to option [0] No Function . Check the fuses
to the frequency converter and mains supply to the unit.
ALARM 37, Phase imbalance
There is a current imbalance between the power units.
ALARM 38, Internal fault
When an internal fault occurs, a code number defined in
Table 7.4 is displayed.
Maintenance, Diagnostics, a... Operating Instructions
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