Troubleshooting:
Check fan resistance.
Check soft charge fuses.
WARNING 25, Brake resistor short circuit
The brake resistor is monitored during operation. If it short
circuits, the brake function is disconnected and the
warning appears. The adjustable frequency drive still
works, but without the brake function. Turn off the
adjustable frequency drive and replace the brake resistor
(see
2-15 Brake Check
).
WARNING/ALARM 26, Brake resistor power limit
The power transmitted to the brake resistor is calculated:
as a percentage, as a mean value over the last 120
seconds, on the basis of the resistance value of the brake
resistor, and the intermediate circuit voltage. The warning
is active when the dissipated braking energy is higher than
90%. If
Trip
[2] has been selected in
2-13 Brake Power
Monitoring
, the adjustable frequency drive cuts out and
issues this alarm, when the dissipated braking energy is
higher than 100%.
Warning: There is a risk of substantial power being
transmitted to the brake resistor if the brake transistor is
short-circuited.
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 adjustable frequency drive 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 adjustable frequency drive 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 parameter 2-15, Brake Check.
ALARM 29, Heatsink temp
The maximum temperature of the heatsink has been
exceeded. The temperature 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 adjustable frequency drive
and the motor is missing.
Turn off 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.
Turn off 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.
Turn off 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 unit cool to operating temperature.
WARNING/ALARM 34, Network communication fault
The network 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 parameter 4-53) or low limit (set in
parameter 4-52). In
Process Control, Closed-loop
(parameter
1-00), this warning is displayed.
WARNING/ALARM 36, Mains failure
This warning/alarm is only active if the supply voltage to
the adjustable frequency drive is lost and
14-10 Line Failure
is NOT set to OFF. Check the fuses to the adjustable
frequency drive.
ALARM 38, Internal fault
It may be necessary to contact your Danfoss supplier.
Some typical alarm messages:
0
Serial port cannot be initialized. Serious hardware failure
Troubleshooting
VLT AQUA 12-Pulse High Power Instruction Manual
8-6
MG.20.Y1.22 - VLT
®
is a registered Danfoss trademark
8
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