Power Consumption Of Bus Devices - Siemens RXB Series Basic Documentation

For internal use only
Siemens
Building Technologies
2.2.2

Power consumption of bus devices

To make the best use of the connectable devices set to "Decentral bus power
supply = Off" and the devices without a bus power supply, it is necessary to
calculate the current requirement from the KNX bus.
Power consumption for Synco devices with "Bus power supply unit = Off".
RMU7x0, RMU7x0B universal controllers
RMH760, RMH760B heating controllers
RMK770 boiler sequence controller
RMB795, RMB795B central control units
RMS705, RMS705B switching & monitoring devices
OZW775 central communication unit
QAX9x3 central apartment unit
Power consumption values for Synco devices without a bus power supply unit:
QAWZ40 room unit
RXB/RXL room controllers
RMZ792 bus operator unit
without external supply
with external AC 24 V supply
OZW771.xx central communication units
OZW772.xx web server
VAV controller GxB181.1E/KN
Room thermostats RDF, RDG, RDU
Room thermostat RDF600KN
Flush-mounted sensor AQR2570
Flush-mounted sensor AQR2576
Room units QMX3.P02, 30, 34
Room units QMX3.P37
Room units QMX3.70, 74
Power consumption values for service interface, coupler and IP router:
OCI700 service interface
Area/line coupler N140/x13
Primary line (main line)
Secondary line (sub-line)
IP router N146 from bus
1)
The Siemens IP router N146 consumes 10 mA from the KNX bus despite the
additional external auxiliary voltage AC/DC 24 V. Power consumption with
auxiliary voltage: 25 mA at DC 24 V, max. 800 mW.
KNX bus communications
Engineering notes
1)
5 mA
5 mA
5 mA
5 mA
5 mA
5 mA
5 mA
7.5 mA
5 mA
45 mA
5 mA
5 mA
5 mA
5 mA
20 mA
5 mA
5 mA
15 mA
7.5 mA
10 mA
15 mA
5 mA
6 mA
8 mA
10 mA
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CE1P3127en
2013-04-08