Platinum remains the most commonly used material in temperature measurement using RTD sensing elements today.
What RTD means?
Resistance Temperature Detector
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.
Where is an RTD used?
Sometimes referred to as resistance thermometers, RTDs are commonly used in laboratory and industrial applications because they provide accurate, reliable measurements across a wide temperature range.
Why Platinum is the most commonly used metal for RTD elements?
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.
Why is platinum used in platinum resistance thermometer?
The most reproducible type of sensor is made from platinum because it is a stable unreactive metal which can be drawn down to fine wires but is not too soft. The length and diameter of the platinum wire used in a thermometer are often chosen so that the resistance of the device at around 0 ºC is 100 ohms.
Where is RTD and thermocouple used?
Both RTDs and thermocouples are sensors used to measure heat in scales such as Fahrenheit and Kelvin.
How is Celsius temperature defined on the scale of a platinum resistance thermometer?
The first term in this expression is the “platinum temperature”, derived by considering that the temperature interval between 0° and 100°C can be divided into equal degrees C of temperature by equating temperature to the electrical resistance of a platinum thermometer in this range, and that the relationship can then
What is the commonly used RTD material explain why?
Platinum is the most commonly used metal for RTD elements due to a number of factors, including its (1) chemical inertness, (2) nearly linear temperature versus resistance relationship, (3) temperature coefficient of resistance that is large enough to give readily measurable resistance changes with temperature and (4)
What is RTD and its types?
Resistance Temperature Detectors (RTDs) available today can generally be categorized into one of two basic typesof RTDs, depending on how their temperature sensing element is constructed. One type of RTD contains thin-film elements and the other type of RTD contains wire-wound elements.
Which type of RTD is used for good accuracy temperature measures?
The most popular RTD is the Pt100. They have been used for many years to measure temperature in laboratory and industrial processes, and have developed a reputation for accuracy, repeatability, and stability. Most RTD elements consist of a length of fine coiled wire wrapped around a ceramic or glass core.
What is the resistance of platinum?
Commercial platinum grades exhibit a temperature coefficient of resistance 0.00385/°C (0.385%/°C) (European Fundamental Interval).
What are the most commonly used RTD elements?
The most common RTD's are made of either platinum, nickel, or nickel alloys. The economical nickel derivative wires are used over a limited temperature range.
Where is RTD used?
industrial applications
What is RTD and 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.
Which are the typesof RTD?
What typesof RTDs are available? There are two main typesof resistance temperature detectors, thin-film and wire-wound.
What is temperature coefficient of resistance for platinum?
The temperature coefficient of resistance of platinum is α=3.92×10-3K-1 at 0∘C.
How do you find the sensitivity of a platinum resistance thermometer?
For a 100Ω platinum RTD with α=0.00385 Ω /Ω /°C and R0= 100Ω, the sensitivity coefficient is computed via the expression 100Ω * 0.000385Ω /Ω /°C = 0.385Ω/°C. Thus, a 100Ω sensor at 0°C will increase its resistance by 0.385Ω in 1°C, or 0.385Ω /°C.