Engineering Documentation

Table Of Contents
Chapter 4 Equipment Controllers
BACnet DXR2 Room Automation Station
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MS/TP Connection
Use recommended 3-wire (1.5-Pair Network Cable [ 36]). Wire the nut shield of both
cables or tie back the shield for the end of line, and terminate the shield at router’s
MSTP port. Connect the yellow reference wire to common terminal 21, the black wire
to terminal 22 and the white wire to + terminal 23. If DXR2.M is at the MSTP cable
end of line, install a 120 Ohm resistor between terminal 22 and + terminal 23.
Observe polarity throughout the MSTP network.
Fig. 70: Connecting MS/TP Port to 3-Wire (1.5 STP) Cable.
Fig. 71: Connecting DXR2.M MS/TP Port to Existing 2-Wire (1 STP) Cable.