Power consumption of bus devices - Basic Documentation - RMK770-1

Communication via the KNX bus

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Air conditioning controller
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Basic Documentation
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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 5 mA
RMH760, RMH760B heating controllers 5 mA
RMK770 boiler sequence controller 5 mA
RMB795, RMB795B central control units 5 mA
RMS705, RMS705B switching & monitoring devices 5 mA
OZW775 central communication unit 5 mA
QAX9x3 central apartment unit 5 mA

Power consumption values for Synco devices without a bus power supply unit:

QAWZ40 room unit 7.5 mA
RXB/RXL room controllers 5 mA

RMZ792 bus operator unit

- without external supply

- with external AC 24 V supply

45 mA
5 mA
OZW771.xx central communication units 5 mA
OZW772.xx web server 5 mA
VAV controller GxB181.1E/KN 5 mA
Room thermostats RDF, RDG, RDU 20 mA
Room thermostat RDF600KN 5 mA
Flush-mounted sensor AQR2570 5 mA
Flush-mounted sensor AQR2576 15 mA
Room units QMX3.P02, 30, 34 7.5 mA
Room units QMX3.P37 10 mA
Room units QMX3.70, 74 15 mA

Power consumption values for service interface, coupler and IP router:

OCI700 service interface 5 mA

Area/line coupler N140/x13

- Primary line (main line)

- Secondary line (sub-line)

6 mA
8 mA
IP router N146 from bus 1) 10 mA

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.