Temperature is the most common of all physical measurements. Temperature sensors are used on circuit boards, as part of thermal tests, in industrial controls, and in room controls such as in calibration labs and data centers. Though there are many types of temperature sensors, most are passive devices: Thermocouples, RTD(resistance temperature detectors), and thermistors.
Temperature sensors are used just about everywhere. There are in the homes we live in, the cars we drive, the schools we learn in. They are even in planes, trains and boats. You will also find them in all sorts of electrical appliances and electronic devices. Refrigerators, stoves, hot water tanks as well as computers, GPS devices and battery chargers all have temperature sensors. Today’s digital medical thermometers, which are used in hospitals and millions of homes every day, all have a temperature sensor in them.
Battery chargers are used to recharge all sorts of batteries, such as car batteries, flashlight batteries and even batteries in your computer. However, battery chargers must be designed so that they don’t overcharge your battery and also so they don’t undercharge your battery.
Because the amount of charge a battery can store varies with temperature, the battery charger must know the battery’s temperature to determine when to stop charging and when to begin charging. In these applications, the temperature sensor is used to turn on or turn off the battery charger.
Your car contains a radiator. In it is a temperature sensor. The reason it is there is to warn you if the water that circulates in your engine becomes too hot. And that’s because if it does, your engine could break and will require that you purchase a new one.
The temperature sensor in your radiator measures the temperature of the radiator to the temperature gauge in your car. As the temperature of the water increases, the temperature sensor creates a larger electrical current to flow. That current flow causes the needle of your temperature gauge to move further to the right.