How does a digital thermometer work?
How does a digital thermometer work?
Digital thermometers rely on the principle that the electrical resistance of metal changes with temperature.
Digital thermometers are different to traditional thermometers such as liquid filled and bi-metal thermometers in that they require a sensor. Typically the sensor used in digital thermometers will be one of the following four:
- Solid State Sensors
- Resistance Temperature Detectors (RTD or PT100)
- Thermistors
- Thermocouples
How do digital thermometers work?
All of these sensors work by producing a resistance, current or voltage in reaction to a change in temperature. These changes are referred to as analogue output signals.
Although all of these digital thermometer sensors provide the same end result in a digital display of the temperature the way they work this out varies.
In basic terms the analogue outputs of these sensors are different.
A microchip is then used to convert this measurement into a temperature reading. This reading is displayed on the screen providing a numerical value to the temperature reading.
