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Note
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Siemens
Building Technologies
11.15 Alarm
Alarms differ in S-mode and LTE mode.
RXB controllers support different alarms:
• Room temperature frost
• Outside air temperature
frost
• Overheating alarm
• Supply air sensor error,
Room sensor error
• PPS2 fault
11.15.1 S-mode
In S-mode, the above described alarms are provided as a common alarm .
The alarm message is mapped to the following S-mode output communication object:
Common alarm (Output communication object)
Flags
Type
R W C T U
1 0 1 1 0 1.005
DPT_Alarm
As soon as the cause of the alarm ceases to exist, the alarm message disappears.
In addition, output Alarm info provides more detailed information:
Alarm info (Output communication object)
Flags
Type
R W C T U
1 0 1 1 0 219.001
DPT_AlarmInfo
Output Alarm info can be enabled or disabled via another communication object:
(this influences also the LTE-Mode alarm signal)
Enable alarm info (Input communication object)
Flags
Type
R W C T U
0 1 1 0 0 1.003
DPT_Enable
RXB (KNX) application library
General and central functions
If the room temperature or the return temperature in a
fan-coil application drops below the fixed frost protection
limit (5 °C or adjustable for outside air applications), an
alarm is generated.
In applications with outside air damper, a safety thermo-
stat in the outside air duct can be connected to the digital
input.
If the digital input of an RXB22.... controller is used as an
overheating alarm (see page 95), the information is
transmitted in this alarm message.
Sensor fault or short circuit.
If the PPS2 communication between a controller and the
room unit is interrupted, or the room unit has an internal
fault, the information is transmitted in this alarm
message.
Send heartbeat
yes
Send heartbeat
yes
Receive timeout States
Ja (fix 42 hours)
FNC Description of functions for FC-10, FC-11, FC-12
States
0 = No alarm
1 = Alarm
Info
See Konnex specification
0 = Disabled
1 = Enabled
CM110385en_05
28 Feb 2009