RTD vs Thermistor: Difference and Comparison

Key Takeaways

  1. Due to their linear resistance-temperature relationship, RTDs provide more accurate temperature measurements than thermistors.
  2. Thermistors respond faster to temperature changes than RTDs, allowing for quick adjustments.
  3. RTDs exhibit better long-term stability and repeatability, making them suitable for applications requiring consistent measurements over time.
RTD vs Thermistor
/10

Science Quiz

Test your knowledge about topics related to science

1 / 10

Which of the following compound is mainly used in hand sanitizer?

2 / 10

Acid turns blue litmus paper into which color?

3 / 10

A bond that occurs between metals and nonmetals is called a/an _______________.

4 / 10

What is the PH of H2O?

5 / 10

A chemical reaction where energy is released is called:

6 / 10

Which of the following gland is present in the human mouth?

7 / 10

Name the fabric which is used in making bulletproof jackets?

8 / 10

Name the process by which the human breathes?

9 / 10

The filament of an electric bulb is made of

10 / 10

Which of the gas is not known as green house gas?

Your score is

0%

What is RTD?

RTD is the abbreviation used for Resistance Temperature Detector. It is defined as the device used to measure temperature change. The principle used in the device RTD is the proportional changes in both resistance and temperature. In other words, the temperature changes when the resistance changes or decreases.

This above statement can be explained through an equation that follows:

R0(1 + a1T + a2T2 + … + anTn)

The device is made up of pure metals like – copper, nickel, platinum, etc. These metals result from used to manufacture RTD devices because they can hold up against high temperatures and have good stability. Despite this advantage, RTD devices show low accuracy. The graph showing the resistance v/s temperature for the RTD device is linear.

rtd sensor

What is Thermistor?

A thermistor is a device that measures temperature changes. They are made of semiconductors, which is why they have positive and negative temperature coefficients. If explained in detail, the temperature increases proportionally with resistance in the case of a positive temperature coefficient. In contrast, in the case of a negative temperature coefficient, the temperature increases are inversely proportional to resistance.

A thermistor can measure the slightest changes in the temperature of the temperature (range -60˚ Celsius to 15˚ Celsius). In contrast, simultaneously, a range of resistors is around 0.5 Ω to 0.75 Ω. It shows a quick response and has a high sensitivity.

The graph showing resistance v/s temperature for the thermistor is non-linear and even comes in a small size. As it has precise accuracy, the price of a thermistor is relatively high. The primary use of a thermistor is to measure the temperature change in home appliances.

thermistor

Difference Between RTD and Thermistor

  1. RTD or Resistance Temperature Detectors are made up of metals like – copper, nickel, platinum, etc., whereas, on the other hand, the thermistor is made up of semiconductors.
  2. The time of response of RTD is relatively slow. In contrast, a thermistor responds quickly to even small temperature changes.
  3. RTDs are said to be less accurate, whereas comparatively, on the other hand, a thermistor is highly precise in detecting minute temperature changes as they have a negative temperature coefficient.
  4. The graph showing resistance v/s temperature for RTD is linear, whereas comparatively, on the other hand, the graph showing resistance v/s temperature for the thermistor is non-linear.
  5. An RTD’s range of temperature is up to 850 ˚ Celsius. On the other hand, the range of temperature measured by a thermistor is 114˚ Celsius and -55˚ Celsius.  
  6. The resistivity of RTD is low, whereas comparatively, on the other hand, the resistivity of a thermistor is high.
  7. RTD is large, whereas, on the other hand, a thermistor is small in size.
  8. The sensitivity of RTD is low compared to that of a thermistor.
  9. The price of an RTD is low, whereas, on the other hand, the price of a thermistor is high.
  10. RTD is mainly used in industries to measure temperature changes, whereas comparatively, the other hand, a thermistor is used at home to measure temperature changes.

Comparison Between RTD and Thermistor

Parameter of ComparisonRTDThermistor
Made up ofMetals like – copper, nickel, platinum, etcSemiconductor
Time of ResponseSlowFast
AccuracyThey are less accurateThey are high in accuracy
GraphIt shows a linear graphIt shows a non-linear graph
Range of TemperatureAbout 850˚ Celsius114˚ Celsius and -55˚ Celsius
ResistivityLowHigh
SizeLargeSmall
SensitivityLowHigh
PriceLowHigh
ApplicationsUsed in industriesUsed in home appliances
References
  1. https://www.emerald.com/insight/content/doi/10.1108/02602280110398044/full/html

Last Updated : 30 July, 2023

dot 1
One request?

I’ve put so much effort writing this blog post to provide value to you. It’ll be very helpful for me, if you consider sharing it on social media or with your friends/family. SHARING IS ♥️

Leave a Comment

Your email address will not be published. Required fields are marked *

Want to save this article for later? Click the heart in the bottom right corner to save to your own articles box!