5/16
Siemens
RXC20, RXC21, RXC22 – Room controllers
CA2N3834en_09
Building Technologies
2013-06-16
The diagram below shows the wiring of the L
ON
W
ORKS
® bus and PPS2 interface when
a QAX… room unit is connected. It also shows the options for connecting the RXT10
commissioning and service tool and the RXT20.1 service terminal.
The yellow service LED shows the current operational status of the room controller by
means of different flashing patterns (see the RXT10 user manual, CM110669).
The service pin is used to identify the room controller in the commissioning phase.
When the pin is pressed the room controller’s identification number is transmitted to the
RXT10 commissioning and service tool.
Disposal
The devices are classified as waste electronic equipment in terms of the European
Directive 2002/96/EC (WEEE) and should not be disposed of as unsorted municipal
waste.
The relevant national legal rules are to be adhered to.
Regarding disposal, use the systems setup for collecting electronic waste.
Observe all local and applicable laws.
Engineering notes
The Desigo RX installation guide, document CA110334, contains the relevant engineer-
ing information for the L
ON
W
ORKS
® bus (topology, bus repeaters, bus termination, etc.)
and for the selection and dimensions of connecting cables for the supply voltage and
field devices.
The room controllers have an AC 230 V mains supply voltage. The controlled devices
(valves and damper actuators) are supplied directly from the room controller.
This means that a separate AC 24 V supply is not necessary for the RXC20, RXC21
and RXC22 room controllers and the associated field devices.
L
ON
W
ORKS
® bus
and PPS2
Service LED
Service pin
