26 Rockwell Automation Publication 1756-RM100F-EN-P - October 2018
Chapter 2 Replacement Considerations with ControlLogix 5580 and GuardLogix 5580 Systems
Project Size
The size of the .ACD file does not reflect the size of your project that 
downloads to the controller. The .ACD file contains multiple components. 
Not all components are downloaded to the controller. 
Configure the Controller
You must consider how to best use controller resources when ControlLogix 
controllers communicate over an EtherNet/IP network. There are limitations 
concerning how much EtherNet/IP communication the controller supports.
Consider the following:
•Connections
•Ethernet Nodes
Connections Overview
A Logix 5000™ controller provides connection resources whenever 
communications are established between two devices.
Connections are used when the system contains the following conditions 
or activities:
• I/O modules, communication modules, and adapters are present in the 
I/O configuration of the user project
• Produced or Consumed tags are configured in the user project
• Connected Messages are executed in the user application
• External devices, programming terminals, or HMIs communicate with 
the controller
You must track the number of connections that are used when you configure a 
ControlLogix 5570 control system.