A Comprehensive Guide: Connecting Allen Bradley and Compactlogix Controllers via Ethernet

Allen Bradley PLC Ethernet Port


In today's digital age, connecting your programmable automation controller (PAC) to Ethernet is vital to leverage the full benefits of remote monitoring, control, troubleshooting, and maintenance. Whether you're working with Allen Bradley or CompactLogix devices, we've got you covered. This comprehensive guide will walk you through the step-by-step process for both.

Gather the Required Equipment

Before you embark on this journey, ensure you have the necessary equipment:

  • Allen Bradley or CompactLogix controller
  • Ethernet cable
  • Computer with Ethernet port (or a USB to Ethernet adapter if needed)
  • Relevant software (RSLinx and RSLogix 500 or Studio 5000 for Allen Bradley; RSLinx Classic for CompactLogix)

Set Up Your Computer

Configuring your computer correctly is the first crucial step. Most PCs have network adapters set up for DHCP by default. Yet to establish a connection with Allen Bradley or CompactLogix Ethernet-enabled devices, it is essential to configure your PC's network adapter with a static IP address within the same subnet as the device. Steps to set a static IP address vary depending on your Windows version, but we'll provide an outline for Windows 7 and XP, which can be adapted for other versions.

Configure IP Address and Subnet for Your Device(s)

Proper configuration of the IP address and subnet for the device is crucial. CompactLogix controllers, such as those from Allen Bradley, can utilize the BootP software utility. Depending on the specific device, you can opt for a manual setup through rotary switches, local HMIs, or USB ports. After completing the setup for Allen Bradley devices, it's important to disable BootP-DHCP to avoid any IP address requests during power cycles.

Configure Your Driver in RSLinx Classic (for CompactLogix) or RSLinx (for Allen Bradley)

RSLinx Classic or RSLinx software facilitates communication between your computer and the PLC. Ensure to configure the appropriate driver for Ethernet communication.

Establish the Ethernet Connection

Now, you're ready to connect your controller to your computer:

  1. Connect one end of the Ethernet cable to the controller's Ethernet port.
  2. Connect the other end of the Ethernet cable to your computer's Ethernet port.

Test the Connection

After setting up the connection, perform the following tests:

  • Open a web browser and enter the controller’s IP address. If the controller's web interface appears, the connection is established.
  • Try accessing the controller's data and perform basic operations to verify the connection's functionality.
  • You can also test the connection by uploading a program to the PLC using RSLinx and RSLogix 500, Studio 5000 (for Allen Bradley), or RSLinx Classic (for CompactLogix).


Connecting your Allen Bradley or CompactLogix controllers via Ethernet is an essential and straightforward process that enhances the functionality of your industrial automation applications. This comprehensive guide should equip you to establish a reliable and efficient connection to your controller, regardless of whether you're a seasoned professional or a beginner in the field. Happy connecting!