Planning Your Cabling Configuration - Allen-Bradley 1779-KFMR User Manual

Planning Your Cabling
Configuration
Terminator
Tap
Dropline
Before installing any hardware, carefully plan your cabling configuration.
The general cabling configuration of a Data Highway II link is shown in
Figure 3.5.
Figure 3.5
Cabling Configuration for a Data Highway II Link
Trunkline
Tap
Node Interface
Each dropline connects one node interface to a tap. Each end of a
trunkline segment connects to a tap. A terminator connects to a tap at
each end of the link to provide the proper terminating impedance
(75 ohms) at each end of the link.
Number of Taps and Length of Trunkline
You require a tap for each node on the link. Also, if you plan to add
nodes later, provide a tap for each future node during initial installation.
This will avoid the disruption of adding taps and rerouting the trunkline
segments after the link is in operation.
A trunkline segment between two taps must be at least 30 cable-feet long.
Chapter 3
Installing Cabling Hardware for
the Data Highway II Link
Terminator
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