A Building Automation System is defined by the Environmental Protection Agency (EPA) as a system that optimizes the start-up and performance of HVAC equipment and alarm systems. A Building Automation System greatly increases the interaction between the mechanical subsystems of a building, improves occupant comfort, lowers energy use, and allows off-site building control.

Building Automation has many different components that are designed to interoperate as one centralized system, giving building managers and engineers more control over their buiilding. These controls can pass information to these managers, allow changes to be made from a centralized location or allow the managers to set points and schedules. At the highest level there are three necessary elements: sensors, controllers and controlled devices.

• Sensors
  Some of the most common include: air quality, fire, smoke, temperature, humidity, pressure flow rate, lighting level and power.

• Controllers
  This component of the system receives a signal from a sensor and compares it to a desired setpoint. Depending on the results the controller may then send out a signal to the controlled device for action.

• Controlled Devices
  This is the terminal device that receives the signal from the controller in which action would occur. These might include: air dampers, mixing boxes, control valves, fans, pumps or motors.

ACIS