Thermostat User Manual

Wire the UCMs
BMTK-SVN01D-EN 29
®
Wire the UCMs
The Comm5 communication link connects unit control modules (UCMs)
to the Tracker termination module. Each controller has one Comm5
communication link. This topic includes information and procedures for
wiring a UCM to a termination module:
Wire specifications
Tracker Comm5 communication-link and sensor wiring is low-voltage
Class 2 wire and must be field-supplied and installed in compliance with
NEC and local codes. To prevent electrical noise interference, all wiring
must comply with requirements outlined in this topic for wire selection
and link-wiring topology.
Trane recommends that you use Level 4 (Echelon) shielded cable for the
Tracker communication link wiring between the Tracker and the Comm5
UCMs to which it communicates. Trane also recommends that you use it
for communication wiring between the VariTrac CCP and its associated
VariTrac or VariTrane UCMs, and for sensor wiring to these devices.
Level 4 cable is available in shielded, plenum and non-plenum versions.
Level 4 cable is available from Trane-approved suppliers as well as other
suppliers. Table 7 on page 30 shows the Trane approved suppliers;
Table 8 on page 31 provides the specifications for Level 4 compliant
cables.
Note:
Do not exceed the maximum number of UCMs that can
communicate on a Tracker controller (see “UCM maximum
capacities for Tracker models 12 and 24” on page 10 for details).