Danfoss VLT AutomationDrive FC 302 Instruction Manual page 135

Warnings and Alarms
WARNING 23, Internal fan fault
The fan warning function is an extra protective function
that checks if the fan is running/mounted. The fan warning
can be disabled in 14-53 Fan Monitor ([0] Disabled).
Troubleshooting
Check fan resistance.
Check soft charge fuses.
WARNING 24, External fan fault
The fan warning function is an extra protective function
that checks if the fan is running/mounted. The fan warning
can be disabled in 14-53 Fan Monitor ([0] Disabled).
Troubleshooting
Check fan resistance.
Check soft charge fuses.
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 adjustable frequency drive is still
operational but without the brake function. Remove power
to the adjustable frequency drive 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 intermediate circuit voltage and
the brake resistance value set in 2-16 AC Brake Max.
Current. The warning is active when the dissipated braking
energy is higher than 90% of the brake resistance power. If
[2] Trip is selected in parameter 2-13 Brake Power
Monitoring, the adjustable frequency drive trips when the
dissipated braking energy reaches 100%.
WARNING
If the brake transistor is short-circuited, there is a risk of
substantial power being transmitted to the brake
resistor.
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 adjustable frequency drive is still
operational but, since the brake transistor has short-
circuited, substantial power is transmitted to the brake
resistor, even if it is inactive.
Remove power to the adjustable frequency drive and
remove the brake resistor.
This alarm/warning could also occur if the brake resistor
overheats. Terminals 104 and 106 are available as brake
resistors Klixon inputs.
MG37A222
Instruction Manual
WARNING/ALARM 28, Brake check failed
The brake resistor is not connected or not working.
Check 2-15 Brake Check.
ALARM 29, Heatsink temp
The maximum temperature of the heatsink has been
exceeded. The temperature fault resets when the
temperature falls below a defined heatsink temperature.
The trip and reset points are different based on the
adjustable frequency drive power size.
Troubleshooting
Check for the following conditions.
For the D, E, and F enclosures, this alarm is based on the
temperature measured by the heatsink sensor mounted
inside the IGBT modules. For the F enclosures, the thermal
sensor in the rectifier module can also cause this alarm.
Troubleshooting
ALARM 30, Motor phase U missing
Motor phase U between the adjustable frequency drive
and the motor is missing.
Remove power from the adjustable frequency drive and
check motor phase U.
ALARM 31, Motor phase V missing
Motor phase V between the adjustable frequency drive
and the motor is missing.
Remove power from the adjustable frequency drive and
check motor phase V.
ALARM 32, Motor phase W missing
Motor phase W between the adjustable frequency drive
and the motor is missing.
Remove power from the adjustable frequency drive and
check motor phase W.
ALARM 33, Inrush fault
Too many power-ups have occurred within a short time
period. Let the unit cool to operating temperature.
Danfoss A/S © Rev. 2014-02-07 All rights reserved.
Ambient temperature too high.
Motor cables too long.
Incorrect airflow clearance above and below the
adjustable frequency drive
Blocked airflow around the adjustable frequency
drive.
Damaged heatsink fan.
Dirty heatsink.
Check fan resistance.
Check soft charge fuses.
IGBT thermal sensor.
9 9
133