Allen-Bradley 1756-L63XT, User Manual

Page: 141 / 212

Rockwell Automation Publication 1756-UM001O-EN-P - October 2014 141
I/O Modules Chapter 8
• If the module has a Real Time Sample (RTS), disable it or set it to a rate
that is greater than the RPI.
• You can add I/O modules until you reach these limits:
– 80% of CPU utilization of the 1756-CN2, 1756-CN2R, or
1756-CN2RXT communication module.
– Less than 400,000 unscheduled bytes per second are displayed in
RSNetWorx for ControlNet software after the network has been
scheduled.
Online Additions—EtherNet/IP Considerations
When you add I/O modules to the EtherNet/IP network, make these
considerations:
• The EtherNet/IP I/O modules that you add can be added as these
connection types:
– Rack-optimized connections, including new and existing connections
– Direct connections
• You can add I/O modules until you reach the limits of the communication
connections of the module.
For EtherNet/IP module limitations, see the EtherNet/IP Modules in
Logix5000 Control Systems User Manual, publication
ENET-UM001 .
Determine When Data is
Updated ControlLogix controllers update date asynchronously with the execution of logic.
Use this flowchart to determine when a producer, such as a controller, input
module, or bridge, sends data.