temperature sensor

A device that detects temperature and converts it into an electrical signal or other forms of output. Temperature sensors are broadly classified into two types: contact and non-contact. Contact type sensors measure temperature by making direct contact with the material, but this has the disadvantage of potentially altering the temperature of the material being measured. Therefore, the material measured must be sufficiently large so that its temperature does not change. On the other hand, non-contact sensors measure infrared radiation emitted from the material, thus avoiding any temperature change. These sensors are often used to activate cooling fans or heating devices in order to maintain the temperature of electrical and electronic equipment within a specified range.