Danfoss VLT AutomationDrive FC 302, Operating Instructions Manual, Page: 114 / 122

If 8-04 Control Word Timeout Function is set to Stop and
Trip , a warning appears and the frequency converter ramps
down until it trips then displays an alarm.
Troubleshooting:
•
Check connections on the serial communication
cable
•
Increase 8-03 Control Word Timeout Time
•
Check the operation of the communication
equipment
•
Verify a proper installation based on EMC
requirements
WARNING 22, Hoist mechanical brake
The report value shows what kind it is.
0 = The torque reference was not reached before time-out.
1 = There was no brake feedback before the time-out.
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 ).
For D, E and F enclosures, the regulated voltage to the fan
is monitored.
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 ).
For D, E and F enclosures, the regulated voltage to the fan
is monitored.
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 frequency converter is still
operational but without the brake function. Remove power
to the frequency converter 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 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
is higher than 90% of the brake resistance power. If
[2] Trip
is selected in 2-13 Brake Power Monitoring , the frequency
converter trips when the dissipated braking power reaches
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 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.
Remove power to the frequency converter and remove the
brake resistor.
This alarm/warning could also occur should the brake
resistor overheat. Terminals 104 and 106 are available as
brake resistors Klixon inuputs, see
Brake Resistor
Temperature Switch in the Design Guide .
WARNING/ALARM 28, Brake check failed
The brake resistor is not connected or not working.
Check
2-15 Brake Check .
ALARM 29, Heat sink temp
The maximum temperature of the heat sink has been
exceeded. The temperature fault does 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
•
Ambient temperature too high
•
Motor cable too long
•
Incorrect airflow clearance above and below the
frequency converter
•
Blocked airflow around the frequency converter
•
Damaged heat sink fan
•
Dirty heat sink
For the D, E and F enclosures, this alarm is based on the
temperature measured by the heat sink sensor mounted
inside the IGBT modules. For the F enclosures, 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 missing.
Troubleshooting
•
Remove power from the frequency converter and
check motor phase U
Warnings and Alarms
VLT
®
Automation Drive FC 300 Operating Instructions
112 MG33U402 - Rev. 2013-12-16
6 6