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Chapter 3 Termination board wiring

The link repeater is limited to 60 devices on either side of the link (120 devices total).

The link repeater requires an earth ground. The installer should be aware of this before making power connections.

Recommended shield connections are shown in Figure 19. Figure 20 on page 39 shows a daisy-chain repeater connection. Follow these guidelines when using a repeater:

Reference the installation information that comes with the link repeater (Comm5 repeater installation, 3270 3285).

Connect the shield-drain wires entering the repeater to a terminal marked with a capacitor symbol. The entering shield-drain wire must be connected to earth ground at the Tracker controller.

Connect the shield-drain wires leaving the repeater to the repeater terminal marked with an earth ground symbol.

Figure 19. Connecting communication link shield wiring to repeater

24 Vac

Transformer

Earth ground

Entering shield. Continuous run, typically starting at the Tracker controller.

Leaving shield. Must be connected to the earth ground terminal on the repeater and terminated (insulated from ground) at the last UCM.

Link Repeater

124 VAC

3

Comm

4

5

6

Comm

7

8

9

Legend

=

Transformer

=

Earth ground

=

Twisted pair, shielded wire

=

Shield ground

per Trane specifications

 

 

 

 

 

38

BMTK-SVN01D-EN

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Image 46
Trane BMTK-SVN01D-EN, Building Automation System manual Connecting communication link shield wiring to repeater