The building management system has evolved significantly from the concept of an automation system overlaid on a separate pneumatic temperature control system. With the advent of direct digital control, it has become a fully integrated automation and control system. Now the distributed microcontroller (application-specific digital controller) extends full functional integration to the most remote zones in the facility.

The functions performed by the building management system (described in this paper) are only as good as its sensing and override capabilities. With communicating microcontrollers in remote occupied zones and on remote eauipment, virtually every controllable point in the building is directly accessible to the building management system -- particularly space temperature setpoint. With zone setpoint control available to the building management system, zone control setpoints are actually reset. The mechanical system remains in control and balanced. Properly integrated, these points can optimize both the local and the central control functions in terms of performance and efficiency. Both building operator and occupant benefit in terms of system efficiency, operating economy, and comfort.