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Siemens  RXC20, RXC21, RXC22 – Room controllers  CA2N3834en_09 
Building Technologies    2013-06-16 
Ordering 
When ordering please specify the quantity, product name, type code and application.  
The controllers are delivered with the basic application 00020, 00021 or 00022, respec-
tively.  
The RXZ20.1 terminal covers are supplied in packs of 1 pair and must be ordered sep-
arately. 
Example: 
30 RXC20.5 room controllers  RXC20.5/00020 
30  Pairs of terminal covers    RXZ20.1 
 
Compatibility  
The QAX… room units and the Siemens field devices can be used with the RXC20, 
RXC21 and RXC22 room controllers.  
For details, refer to the RX hardware overview, CA2N3804. 
 
Design 
The RXC20, RXC21 and RXC22 room controllers consist of a housing base, a housing 
cover and the printed circuit board with connection terminals. The controller also has a 
tool socket, a service LED and a service pin. 
 
Plug-in Connection terminals
Housing cover
Plug-in Connection terminals
70198
 
Cable restraints 
 
Plug-in  
connection terminals 
for L
ONWORKS® bus 
 
Housing base 
 
 
 
Service LED 
 
Service pin 
Tool socket 
 
Terminal covers (RXZ20.1) are available as an option, to protect the connection termi-
nals from physical contact and dirt. The service LED remains visible when the terminal 
covers are in place, and the service pin can be operated with a pointed implement. The 
cable is connected to the room controller by breaking out the perforated cable entry 
guide. 
 
70200
  Removing the terminal cover 
 
Terminal cover