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Technical Information
▪
Low cabinet temperature (critical):
When the cabinet temperature sensor is not used, this alarm can
be deactivated (
22 “Cabinet temperature” alarm enabled
).
This alarm is triggered when the cabinet
temperature falls below the threshold (
23 “Low cabinet temperature” alarm threshold
) for a certain
time. (
25 “Cabinet temperature”
alarm delay
). When this fault occurs, refrigeration operation is
stopped and the system enters the alarm condition.
▪
Low control temperature (critical):
Is triggered when the control temperature falls below the
configured setpoint by more than the amount configured in the parameter
19 “Low temperature”
alarm threshold
for a certain time (
18 “Low temperature” alarm delay
). When this fault occurs,
refrigeration operation is stopped and the system enters the alarm condition.
▪
High control temperature:
Is triggered when the control temperature exceeds the configured setpoint
by more than the amount configured in the parameter
17 “High temperature” alarm threshold
for a
certain time (
16 “High temperature”
alarm delay
).
▪
Defrost terminated by time:
This alarm is triggered when the defrost temperature is not reached
within the permissible time delay (
30
“Day Defrost termination time”
respectively
31
“Night Defrost
termination time
”
). It has no additional effects on system controls. This alarm is canceled with the
start of the next defrost cycle.
▪
Discharge temperature too high (critical):
This alarm is triggered when a discharge temperature
sensor is present and the maximum temperature is exceeded for 10 seconds (typical value: 120°C).
When this fault occurs, refrigeration operation is stopped and the system enters the alarm condition.
▪
Timeout valve opening 100%:
This alarm is only considered when an EXV is present. This alarm is
triggered when the valve is opened 100% for more than 10 min. This may indicate a lack of refrigerant
in the system.
▪
High condensing pressure (critical):
This alarm is only considered when the high pressure sensor
is available. This alarm is triggered when the condensing pressure remains above the threshold
configured in the parameter
20 “High condensing pressure” alarm threshold
. A delay time is
entered by the
21 “High condensing pressure” alarm delay
parameter. This alarm is not triggered
if there is a condensing pressure sensor failure. When this fault occurs, cooling is stopped and the
hybrid fan is turned on.
▪
Bus/gas alarm:
In the event of a bus alarm, the hybrid fan is activated irrespective of compressor
operation or defrost cycle. Should no bus alarm apply any longer, the hybrid fan controls return to
normal operation.
▪
Configuration alarm (critical):
If there is a conflict in configuration this alarm is triggered. Possible
configuration conflicts are:
▪
Variable speed can only be used with R290 refrigerant
56 Refrigerant
▪
Envelope alarm (critical):
Operating point is running out of the compressor envelope This alarm is
only evaluated if a variable speed compressor is configured
▪
Compressor alarm (critical):
This alarm is triggered if Modbus communication to a compressor
controlling device (Softstarters, Drive) is lost. The alarm is only triggered if a compressor command
type
121 compressor command type
different to relays is configured
9.3
Critical alarms
If one of the alarms classified as "
critical
" occurs, the system enters the alarm condition. The compressor
turns off and the defrost process is stopped if it is currently ongoing. The system returns to normal operation
when all critical hardware alarms have been resolved. The critical software alarms are automatically canceled
when the compressor stops.
If the alarm was triggered during compressor operation, the system only returns back to normal controls after
an
“Alarm pause“
delay time.
