A temperature transducer is an electrical device usually used in automated air-temperature control sequences. Its purpose is to take a measurement of the air temperature and relay the information — after translating it into a readable form — to a power source for the mechanical part of the system. Once the information has been taken by the temperature transducer and relayed, the information is sent to the unit power source. Usually, when a transducer is telling a mechanical unit, such as a furnace or a cooling system, that it needs to engage in order to create the desired temperature, it will also tell the unit when it has reached that desired temperature. This signals the unit to disengage, allowing for the efficient operation of many central air or heating units.
When the unit power source reveals the information from the temperature transducer, it either tells the system to stand idle or engage depending on the temperature that has been measured. If the temperature reads lower than the setting input to the system by the user, the heating unit is told to engage until the air is measured by the temperature transducer to be as high in temperature as the user desires. The same principle is applied to cooling systems, however in these cases the temperature is read to be higher than the setting input before the cooling system is engaged.
Temperature transducers send the information they collect to more sources than just the power source for the heating or cooling unit. Digital thermostats installed in many households and businesses utilize digital LCD screens to display the information that is read by the temperature transducer. The transducer measures the air temperature and translates it into information the screen is able to display at the same time the information is being sent to the power source telling it whether or not to engage.
These transducers can also be used in a number of useful applications, from telling an individual the outside temperature from inside the house or building, to informing researchers at what temperature a certain chemical or physical reaction happens. The transducer itself is basically a sensor that has the ability to transfer the information it obtains to another medium in a form different than it was originally read. This information can be translated back to a digital screen, without having to tell any sort of mechanical unit to actuate, disengage, or take no action.