During the last decade, growth in the building industry and the increasing complexity of building control systems has necessitated centralized control centers for building control systems management. For large buildings and building complexes, the annual maintenance and operating cost can be appreciable. Building automation centers permit closer supervision of building conditions and recognize problem areas in a relatively short time. The definite savings and convenience of building automation centers have made the automation systems widely accepted.

The total building control or building automation concept is basically a centralized console which receives building variables such as temperature, pressure, humidity, fan & motor running status, etc., and it indicates the use of alarms accordingly. The operator can, therefore, investigate building variables without physical presence at the sensor location. Most building automation centers may be equipped with two-way voice communication equipment. This permits the console operator to communicate with different locations in the building.

Building automation centers come in various sizes. There are small systems for small buildings of approximately 100 point capacities. The indicators, are simply a panel of pilot lights. Large building-automation centers, such as computer-based total building systems, include a building monitoring system and a fire and security system