Danfoss VLT Series Design Manual page 171

VLT ® HVAC Drive Design Guide
ALARM 16, Short-circuit:
There is a short-circuit in the motor or on the
motor terminals.
Turn off the adjustable frequency drive and
remove the short-circuit.
WARNING/ALARM 17, Control word
timeout:
There is no communication to the adjustable
frequency drive.
The warning will only be active when par. 8-04
is NOT set to
If par. 8-04 is set to
appears and the adjustable frequency drive
ramps down to zero speed, while giving an
alarm.
Par. 8-03
possibly be increased.
WARNING 24, External fan fault:
The fan warning function is an extra protec-
tion function that checks if the fan is running/
mounted. The fan warning can be disabled in
Fan Monitor
WARNING 25, Brake resistor short-
circuited:
The brake resistor is monitored during opera-
tion. 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 ad-
justable frequency drive and replace the brake
resistor (see par. 2-15
ALARM/WARNING 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 s based on the resistance
value of the brake resistor (par. 2-11) and the
intermediate circuit voltage. The warning is
active when the dissipated braking energy is
higher than 90%. If
in par. 2-13, the adjustable frequency drive
cuts out and issues this alarm, when the dis-
sipated braking energy is higher than 100%.
WARNING/ALARM 27, Brake chopper
fault:
The brake transistor is monitored during op-
eration, and if it short-circuits, the brake func-
tion disconnects and the warning is issued.
The adjustable frequency drive is still able to
run, but since the brake transistor has short-
OFF
.
Stop and Trip
, a warning
Control Word Timeout Time
, par. 14-53, (set to [0] Disabled).
Brake Check ).
Trip
[2] has been selected
MG.11.B4.22 - VLT ® is a registered Danfoss trademark.
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.
Warning: There is a risk of sub-
stantial power being transmit-
ted to the brake resistor if the
brake transistor is short-circuit-
ed.
ALARM/WARNING
failed:
Brake resistor fault: the brake resistor is not
connected/working.
could
WARNING/ALARM 29, Drive overtem-
perature:
If the enclosure is IP 20 or IP 21/TYPE 1, the
cut-out temperature of the heatsink is 203
+10 o F [95 o C +5
cannot be reset until the temperature of the
heatsink is below 158
The fault could be a result of:
- Ambient temperature too high
- Motor cable too long
ALARM 30, Motor phase U missing:
Motor phase U between the adjustable fre-
quency 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 fre-
quency 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 fre-
quency drive and the motor is missing.
Turn off the adjustable frequency drive and
check motor phase W.
ALARM 33, Soft-charge fault:
Too many power-ups have occurred within a
short time period. See the chapter
Specifications
for the allowed number of pow-
er-ups within one minute.
WARNING/ALARM 34, Serial communi-
cation bus fault:
The serial communication bus on the commu-
nication option card is not working.
8. Troubleshooting
28, Brake check
o F
o C]. The temperature fault
o F [70 o C].
General
8
171