In the IoT, another type of device, called a sensor, must be connected to the data network. A sensor is an object that can be used to measure a physical property, and convert that information into an electrical or optical signal. Examples of sensors include those that can detect heat, weight, motion, pressure, and moisture.
Sensors are typically purchased with pre-programmed specific instructions; however, some sensors can be configured to change their degree of sensitivity or the frequency of feedback. The sensitivity setting indicates how much the sensor's output changes when the measured quantity changes. For example, a motion sensor can be calibrated to detect the motion of people, but not pets. A controller, which may include a graphical user interface (GUI), is used to change sensor settings, either locally or remotely.
Table _unit3.2.1 Table 5
|Oil, gas, mining||Cities||Transportation||Utilities||Agriculture|
|Sensors detect chemical levels such as carbon monoxide, carbon dioxide, oxygen, methane, hydrogen, ammonia, and hydrogen sulfide.||Some sensors include pressure (for parking), dust concentrations, noise, displacement of cracks, temperature, humidity, and luminosity.||Sensors measure idle times, fuel usage, engine faults, and engine load.||Sensors measure idle times, fuel usage, engine faults, and engine load.||Sensors detect soil moisture, leaf wetness, solar radiation, atmospheric pressure, and stem diameter.|