What is a RTD temperature sensor?

An RTD (Resistance Temperature Detector) is a sensor whose resistance changes as its temperature changes. The resistance increases as the temperature of the sensor increases. The resistance vs temperature relationship is well known and is repeatable over time. An RTD is a passive device.

How is RTD used to measure temperature?

An RTD is a temperature sensor which measures temperature using the principle that the resistance of a metal changes with temperature. In practice, an electrical current is transmitted through a piece of metal (the RTD element or resistor) located in proximity to the area where temperature is to be measured.

What is the difference between an RTD and a thermistor?

RTD is a type of wire whose resistance changes with change in its temperature. A thermistor is a temperature sensitive resistor whose resistance varies with temperature variation. RTD is made of pure metals like platinum, nickel, or copper. Thermistors are made up of ceramic or polymer materials.

What is the difference between an RTD and a thermocouple?

An RTD utilizes the change in resistance of the metal to predict the change in temperature. While thermocouple is a thermoelectric sensor that uses the change in voltage/ emf to get the change in the temperature. RTD generally operates in the range between -200 to 600° C.

How do RTD sensors work?

An RTD works by using a basic principle; as the temperature of a metal increases, so does the resistance to the flow of electricity. An electrical current is passed through the sensor, the resistance element is used to measure the resistance of the current being passed through it.

When would you use an RTD?

The conclusion is based exclusively on the advantages and disadvantages of the sensor types, and does not consider the features and benefits of the measuring equipment. For applications that require a high accuracy and operate at temperatures below 500 °C, the RTD temperature sensors are often the right choice.

What is RTD example?

Some of the examples of RTD sensor are coolant sensor, transmission oil temp. sensors, intake air temperature sensor, fire detectors, etc.. Due to their accuracy and stability, RTD sensors are rapidly replacing thermocouples in industrial applications. RTD can give higher accuracy values.

Why Pt is used in RTD?

Platinum film is used in the construction of RTDs because it is stable, provides repeatable and measurable results and has a broad temperature range. The way RTDs are constructed makes them more rugged and reliable in harsh conditions which is why it can be used in industrial and critical applications.