Termination Resistance Placement For Comm5 Links - Trane Tracer MP581 Hardware Installation

Chapter 7 Wiring Comm5 links
Figure 22. Alternate daisy chain configuration
Device
Device
42
Device
Repeater
System Device
panel
Figure Note:
•
Repeater with system panel in the middle of the link
•
Maximum wire length for Comm5 is 4,500 ft (1,400 m) on each side of the
repeater
•
For termination resistor placement, see "Termination resistance placement
for Comm5 links" on page 42
Termination resistance placement for
Comm5 links
Termination resistors are required at each end of Comm5 communication
daisy chain links.
To correctly place termination resistors follow these guidelines:
Terminate a daisy chain configuration with a resistor at each end of
•
the link (see Figure 23 on page 43):
—22 AWG Level 4 wire 105
—18 AWG Trane "purple" wire 82
If a repeater is used, each link of the configuration that is created by
•
the repeater requires termination resistors (see Figure 24 on
page 43).
Trane recommends that only one type of wire be used for the Comm5
•
communication link.
A set of as-built drawings or a map of the communication wire layout
•
should be made during installation. Any sketch of the communication
layout should feature the terminating resistor placement.
Device
Device
Ω, 1%, 1/4
Watt
Ω, 1%, 1/4
Watt
CNT-SVN01C-EN