22 Rockwell Automation Publication CNET-UM001F-EN-P - February 2018
The UMAX is the highest network address of a node that can
communicate on a ControlNet network. The UMAX must be set equal
to or higher than the SMAX.
• Assumed maximum cable lengths and maximum number of repeaters
With this default ControlNet network, you can have unscheduled
communication between the various devices on the network by using Logix
Designer application and RSLinx software.
Important:
To improve performance, configure a ControlNet network with RSNetWorx for ControlNet software. We
recommend these settings:
• Set the Unscheduled Maximum Node Address (UMAX) equal to the highest node address on the network.
Leaving this parameter at the default value of 99 wastes bandwidth and reduces system performance.
• Set the Scheduled Maximum Node Address (SMAX) to a value three or four above the highest scheduled
node address, so you can expand the network in the future.
Also, be aware that each skipped node will subtract a small amount of bandwidth from the network.
When planning a ControlNet network, consider these factors:
• Topology
• Number of nodes
• Distances
• Connections
A ControlNet network supports a variety of topologies, including
trunkline/dropline, star, tree, and ring redundancy. In its simplest form, a
ControlNet network is a trunkline to which you connect nodes with a tap and
a one-meter dropline.
Figure 5 - Example ControlNet Network Trunkline/Dropline Topology
Item Description
Trunkline
Node
Tap with dropline
Capacity and
Topology
To Next Page
Loading...
