Beckhoff PC uses software to communicate with Allen-Bradley CompactLogix or ControlLogix. The software is called TwinCAT EthernetIP Slave. Without this software, Allen-Bradley can not get Beckhoff PC’s information. However, I could not find any document on how to check it. With help from Beckhoff technical support, I figured it out and wanted to show it here.
Check Beckhoff TwinCAT EthernetIP Slave
Use CERHost to get online with the Beckhoff PC or just get to the Control Panel on Beckhoff PC with keyboard and monitor.
Click on the Remove Programs. If Beckhoff TwinCAT EthernetIP Slave is in the program list (as shown below), then you have it.