#WishIknew – How does an RTD work?

Temperature

When you have a question about process automation that needs a short answer, let us know with #WishIknew and @Visaya! We’ll reply with a #WishIknew post. It’ll give a quick explanation, then some related articles, videos, or reviews if you want to know more.

Wish I knew how an RTD works!

Let’s start at the beginning. RTD means resistance temperature detector, and you’ll find these sensors used in many sectors to measure temperature.

Image of RTD types
Courtesy of rktempsensor

As the name says, it uses changes in resistance to detect temperature.  When the temperature increases, the RTD’s resistance increases, and vice versa.

Vendors build these sensors out of a variety of materials. Platinum, copper, and nickel show up the most often, with platinum as the fan favorite because it offers the best stability in a wide range of temps.

You can choose RTDs with two, three, or four wires, but what does that mean? These wires create the compensation you need for the cable. Of course, the two-wire option doesn’t, so you should choose it when you need only an approximate value. The three-wire option is most common in many applications.

Image of RTD wiring
Courtesy of instrumentationtools

We have an article here at Visaya discussing RTDs and other types of temperature sensors. And on the right, you can explore the market with our device page. Then, if you want to learn more about a device, we have a bunch of product reviews and comparisons.

This video will tell you more about RTDs:

 

Related tags: #WishIknew Basic devices English Measurements Principle RTD Temperature
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#WishIknew - How does an RTD work?
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