This part of this European Standard specifies the requirements for the hardware to perform the tasks within a BACS. This part of this European Standard provides the terms, definitions and abbreviations for understanding of Part 2 and Part 3. Part 2 relates only to physical items/devices, i.e.: - operator stations and other human system interface devices; - devices for management functions; - control devices, automation stations and application specific controllers; - field devices and their interfaces; - cabling and interconnection of devices; - engineering and commissioning tools. This part of this European Standard shows a generic system model to which al