WARNING/ALARM 27, Brake chopper fault
The brake transistor is monitored during operation and if it short-circuits,
the brake function disconnects and issues a warning. The frequency con-
verter is still able to run, but since the brake transistor has short-circuited,
substantial power is transmitted to the brake resistor, even if it is inactive.
Turn off the frequency converter and remove the brake resistor.
This alarm/ warning could also occur should the brake resistor overheat.
Terminal 104 to 106 are available as brake resistor. Klixon inputs, see
section Brake Resistor Temperature Switch.
WARNING/ALARM 28, Brake check failed
Brake resistor fault: the brake resistor is not connected or not working.
Check par. 2-15
Brake Check
.
ALARM 29, Heatsink temp
The maximum temperature of the heatsink has been exceeded. The tem-
perature fault will not be reset until the temperature falls below a defined
heatsink temperature. The trip and reset point are different based on the
drive power size.
Troubleshooting:
Ambient temperature too high.
Too long motor cable.
Incorrect clearance above and below the drive.
Dirty heatsink.
Blocked air flow around the drive.
Damaged heatsink fan.
For the D, E, and F Frame Drives, this alarm is based on the temperature
measured by the heatsink sensor mounted inside the IGBT modules. For
the F Frame drives, this alarm can also be caused by the thermal sensor
in the Rectifier module.
Troubleshooting:
Check fan resistance.
Check soft charge fuses.
IGBT thermal sensor.
ALARM 30, Motor phase U missing
Motor phase U between the frequency converter and the motor is miss-
ing.
Turn off 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.
Turn off 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 miss-
ing.
Turn off the frequency converter and check motor phase W.
ALARM 33, Inrush fault
Too many power-ups have occurred within a short time period. Let unit
cool to operating temperature.
WARNING/ALARM 34, Fieldbus communication fault
The fieldbus on the communication option card is not working.
WARNING/ALARM 35, Out of frequency range:
This warning is active if the output frequency has reached the high limit
(set in par. 4-53) or low limit (set in par. 4-52). In
Process Control, Closed
Loop
(par. 1-00) this warning is displayed.
WARNING/ALARM 36, Mains failure
This warning/alarm is only active if the supply voltage to the frequency
converter is lost and par. 14-10
Mains Failure
is NOT set to OFF. Check
the fuses to the frequency converter
4 Troubleshooting VLT
®
HVAC Drive Programming Guide
272
MG.11.C9.02 - VLT
®
is a registered Danfoss trademark
4