Trane BACnet MS/TP Installation, Operation And Maintenance Manual page 14

Best Practices
Meet requirements when adding zone sensor communication stubs to a Tracer
UC400/Symbio™ 500.
The wire that runs from a zone sensor to a unit controller is commonly referred to as a communication stub.
Figure 8
the BACnet
that the zone sensor includes the optional communication module.
Any or all unit controllers on a link can be wired with a communication stub. Unlike LonTalk
is no limit on the number of unit controller communication stubs. Polarity must be maintained and the
length limit is 600 ft (183 m).
For ease of use, the wire for the communication stub can be the same as that used for BACnet
communication link wiring as described in
Figure 8. Zone sensor communication stubs on Tracer
+
Tracer
®
BACnet Terminator
Note: UC400 is shown, but this applies to Symbio™ 500 as well.
14
shows an example of communication stub-wiring to a BACnet
®
link; it is a wire that runs from the Tracer
®
SC+
®
UC400 IMC link down to the zone sensor. Ensure
"Configuring and Wiring the BACnet® MS/TP Link," p.
®
UC400/Symbio™ 500
IM
+
VDC
BI LINK IMC
AI AI AI AI AI
P P
LINK IM
TX
RX
SERVI
SERVICE TOOL
®
Tracer UC400
Zone sensors
®
device. The stub is not part of
®
links, there
The zone sensors are wired into
the IMC terminals on the Tracer
UC400/Symbio™ 500 controller
IM
+
VDC
BI LINK IMC
AI AI AI AI AI
P P
LINK IM
TX
RX
SERVI
SERVICE TOOL
®
Trace r UC400
BAS-SVX51L-EN
®
®
8.
®