Trane Tracer Summit Hardware And Software Installation Manual page 90

BMTW-SVN01F-EN
Commercial Self-Contained (CSC) and IntelliPak CSC Interfaces
To connect the shield:
Connect the shield at the BCU (TB2) to provide a drain for RFI/EMI, and
then splice it with other CSC UCM shields at the CSC UCM end. Tape
the shield at the last CSC UCM in the chain to prevent any connection
between the shield and ground (see Figure 36 on page 76).
Note:
Observe the polarity throughout communication links.
IMPORTANT
UCM ground loops will cause a malfunction.
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