Order Components; General Planning; Segment Planning; Link Planning - Rockwell Automation Allen-Bradley ControlNet 1734-ACNR User Manual

Order Components

Now that you are ready to begin ordering components, use these guidelines to
help you select components.

General Planning

The ControlNet cable system is isolated from earth and must be protected
from inadvertent ground connections.

Segment Planning

• all connections to the trunk cable require a tap
• taps may be installed at any location on the trunk cable
• tap drop-cable length must not be changed (fixed at 1 meter)
• maximum number of taps = 48, with 250 m (820 ft) of standard RG6
trunk cable
• maximum trunk-cable length of standard RG6 trunk cable = 1000 m
(3280 ft), with 2 taps
• 75Ω trunk terminators are required on both ends of a segment
• one tap with an unconnected drop cable may be installed for
maintenance purposes
• use ControlNet tap terminators (1786-TCAP) for all other unconnected
drop cables
• use BNC bullet connectors at future tap locations
• do not mix redundant and non-redundant nodes when redundant
cabling is desired
• avoid high noise environments when routing cables

Link Planning

• maximum of 99 nodes (excluding repeaters)
• repeaters require a tap but are not counted as nodes — they are included
in the number of devices allowed per segment (48)
• repeaters may be installed at any tap location along a segment
• there can only be one path between any two points on a link
• the configuration of both sides of a redundant segment must be the
same
• the total cable difference between the two sides of a redundant link can
not exceed 800 m (2640 ft)
Determine Your ControlNet Media Requirements
Publication CNET-UM001C-EN-P - November 2005
C-23