Rockwell Automation Allen-Bradley ControlNet 1786 Series, Руководство по установке

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Publication CNET-IN002A-EN-P - December 2001
3-20 Install a ControlNet Coax Media System
Terminate Segments
The taps on the ends of the segment have only one cable connector
attached to them. This leaves an open, or unterminated, end on the
segment. Signals transmitted along the cable will reflect off these
unterminated ends and interfere with transmission.
To eliminate signal reflections from the ends of the segment, you must
attach a 75
Ω
terminator 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.
5. Connect one end of the trunk-cable section to one of the tap’s
BNC connectors.
6. Install a 75
Ω
terminator onto the tap’s other BNC connector.
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Repeat steps 1 and 2 at the other end of
the segment
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1786-XT