Rockwell Automation 1786-series ControlNet Coax Media Planning and Installation Guide - Manual (Page 60)

60 Publication CNET-IN002B-EN-P - June 2010
Chapter 3 Install a ControlNet Coax Media System
Connect Cable Sections Connect the cable sections to the tap’s BNC connectors.
Terminate Segments The taps on the ends of the segment have only one cable connector attached
to them. This leaves an open, or un-terminated, end on the segment. Signals
transmitted along the cable reflect off these un-terminated ends and interfere
with transmission.
To eliminate signal reflections from the ends of the segment, you must attach a
75
Ω
terminating resistor to the first and last taps on the segment. The terms
first and last refer to the physical location of the node along the trunk cable.
1. Connect one end of the trunk-cable section to one of the tap’s
BNC connectors, as shown in the above illustration.
2. Install a 75
Ω
terminating resistor onto the tap’s other BNC connector.
3. Repeat steps 1 and 2 at the other end of the segment.
20078
TIP
The bend radius is 1.5 in. for all fixed-tap drop cables.
Terminating Resistor BNC Plug
20079