Key Components of Building Automation Systems
Modern control systems have three necessary elements: sensors, controllers, and the controlled devices.
| Component | Description |
|---|---|
| Sensors | There is an increasing variety and level of sophistication of sensors available for use with modern control systems. Some of the more common include: temperature, humidity, pressure, flow rate, and power. Sensors that track indoor air quality, lighting level, and fire or smoke are becoming more common. |
| Controllers | The function of the controller is to compare a signal received from the sensor to a desired setpoint, and then send out a corresponding signal to the controlled device for action. Controllers may be very simple, such as a thermostat where the sensor and controller are usually co-located, to very sophisticated microprocessor based systems capable of powerful analysis routines. |
| Controlled Devices | The controlled device is the terminal device receiving the signal from the controller. Amongst others, typical controlled devices include: air dampers, mixing boxes, control valves, and in some cases, fans, pumps, and motors. |