The CI871K01 is a communication interface module designed by ABB5. It serves as an AC 800M communication interface, connecting to Profinet IO devices via Ethernet. It uses the Profinet IO protocol, enabling seamless data exchange with other devices supporting this protocol, thus facilitating real – time monitoring and control within the system5. The module comes with a TP867 baseplate, which has two RJ45 Ethernet connectors, with only the CH1 connector supporting 100 Mbps being utilized for Profinet IO connection. The Ethernet cable should be linked to the Profinet IO network through an Ethernet switch. The CI871 expansion unit houses the CEX – bus logic, a communication unit, and a DC/DC converter that provides the necessary voltage from a +24 V supply through the CEX – bus. It features a modular design, ensuring easy integration into existing industrial automation systems5. Additionally, it supports functions such as hot – swapping and online reconfiguration, contributing to the high availability and maintainability of the system4.