System 800xA’s S800 I/O is a distributed, highly modulated and flexible I/O system, providing easy installation of I/O modules and process cabling. S800 I/O modules and termination units can be mounted and combined in many different configurations to fit space requirements or meet any application. A comprehensive assortment of I/O modules and accessories are available for safety critical and non-critical use. Within the S800 I/O family, there are SIL3 compliant modules that can be used for safety critical applications.

The High Integrity I/O is certified for IEC 61508-SIL3, DIN V 19250/DIN V VDE 0801-AK6 and EN954-1 Category 4. The High Integrity I/O has to be used together with a certified controller to comply with the standards. There are three modules that belong to the High Integrity I/O family that are certified for these standards, AI880/AI880A, DI880 and DO880. The modules are supported by the AC 800M controller PM865 only and have to use the optical ModuleBus modem TB840 when adding optical clusters.