IC697CMM742 GE Fanuc Series 90-70 Ethernet Communications Module

Product Role & System Fit

Within a Series 90-70 PLC rack, the IC697CMM742 occupies a clearly defined role: it is the primary Ethernet interface between the controller and the outside world. Installed in a standard VME slot, it communicates with the CPU across the backplane while independently managing network traffic.

This separation ensures that communication delays or network issues do not interfere with core control logic. The CPU continues executing the program deterministically, while the communications module handles packet transmission, session management, and protocol handling. For system integrators, this architecture provides confidence that adding network connectivity will not compromise control performance.

Compatibility is another strong point. The IC697CMM742 works alongside a wide range of Series 90-70 CPUs and I/O modules, making it suitable for both new system builds and retrofits. In mixed environments, it often serves as the connection point between older PLC logic and newer visualization or data-logging platforms.

In redundant or distributed systems, multiple Ethernet modules may be used to segment traffic or provide alternative data paths. Engineers sometimes dedicate one Ethernet connection to SCADA communication and another to PLC-to-PLC data exchange, improving clarity and reliability. The module’s predictable behavior makes such architectures easier to design and support.

Ultimately, the IC697CMM742 fits best in systems where long-term stability and compatibility matter more than chasing the latest networking trends. It reflects an era of industrial automation where robustness and clarity were prioritized—and those qualities remain relevant today.