A sensor is an electronic device that detects any change in a particular physical condition and converts it into an electronic signal. In an electronic system, the sensor is the first point of contact with the environment. Consequently it is vital to any measurements. Subsequently sensors give readouts, or send the information on to another component in the system. Our medical, space exploration, military, scientific and industrial sectors all use a vast array of sensors. Furthermore the technology keeps advancing and news ones appear all the time.
Some sensors require an external power supply, such as the mains electricity.
However some sensors work without a power supply. This is due to obtaining their energy from whatever they are measuring.
Depending on whether it's for home or commercial uses, sensors can measure just about anything you can imagine. Heat, humidity, speed, sound, movement, electric current, human biometric features, pressure, vibration and light level are just some some examples of sensor types.
Here are just a few examples to get you started.
The possibilities open up into automation, which is discussed in the next section.
The range of places to install sensors is vast. It depends on what they are being used for.
Firstly in the home, you'd use them for controlling household appliances for the sake of safety, comfort and energy efficiency. In business you'd use them for some of the same purposes. However the scale of your business and the type of industry would require more functions and combinations than a residential home.
One of the most exciting uses for this technology is in automation.
This is where you link many technologies into one intelligent system of environmental control or monitoring of safety and security. In effect it is an intelligent network, continually adjusting the conditions in your premises. Although it's automatic, you have ultimate control, sometimes with just the press of a button.
See also Smart Home Automation