The SIEMENS 6GK7443-1EX02-0XE0 is a Communications Processor Module from the SIAMETIC NET CP 443-1 range. It connects a SIMATIC S7-400 to Industrial Ethernet via TCP/IP and ISO protocols, supporting S7 communication, fetch/write, and send/receive with or without RFC. This is the module that puts your S7-400 on the plant network — no extra gateway needed.
The module handles Industrial Ethernet connectivity for the S7-400 rack. It processes TCP/IP and ISO transport, runs S7 communication for controller-to-controller or HMI links, and supports fetch/write and send/receive services for data exchange with third-party systems. The RFC option means it can handle raw data frames for custom application layers.