GB/T 26804.5-2011

This standard specifies the technical requirements, test methods, and inspection rules for digital input/output (I/O) channel modules used in industrial control computer systems. It is applied in manufacturing automation and process control environments to ensure the reliability and interoperability of modules that interface with sensors, actuators, and other discrete devices. The standard is particularly relevant for system integrators and equipment manufacturers designing or verifying digital I/O modules for programmable logic controllers (PLCs) and distributed control systems (DCS).