Rockwell Automation 1770 DH,DHII,DH485 CABLE - Manual (Page 19)

Planning a Data Highway or Data Highway Plus
Cable System
Chapter 2
2-3
Trunkline
The trunkline is the bus, or the central part of the network cable system.
The length of the trunkline depends upon the location of the nodes in your
network, however, the maximum length for the trunkline is 10,000 feet
(3050 meters).
The trunkline is constructed of Belden 9463 twinaxial cable (Figure 2.2).
This cable consists of a twisted pair of conductors wrapped in two layers of
shielding and a drain wire.
Figure 2.2
The trunkline and droplines are constructed of Belden 9463
Twinaxial Cable.
Insulation
Clear
Conductor Wire
Blue
Conductor Wire
Filler Cord
Insulation
Drain
Wire
Braided Shield
Foil Shield
Outer Jacket
Filler Cord
11606
You can order Belden 9463 twinaxial cable from Allen-Bradley in
increments of 100 feet (30.5 meters). The catalog number is 1770-CD.
For information on installing the trunkline, refer to Chapter 3.
Droplines
Droplines connect nodes to the trunkline. The length of droplines depends
upon your network’s specific needs, however, each dropline must be no
more than 100 feet (30.5 meters) long. If possible, keep the dropline cables
longer than 10 feet (3.0 meters) in length.
Like the trunkline, droplines are constructed of Belden 9463
twinaxial cable.
For information on installing the droplines, refer to Chapter 3.