Technical Blog

Advantages of RTD sensors

What is an RTD Sensor?

RTD stands for Resistance Temperature Detector, they measure temperature through resistance; the resistance value will increase as the temperature increases.

RTDs are usually constructed of platinum, nickel or copper. RTD specifications include a base resistance value and a temperature cfficient of resistance value (or TCR). The base resistance value indicates the nominal resistance of the RTD at 0˚C for nickel and platinum or 25˚C for copper constructions, it typically ranges from 10 to several thousands of Ohms (Ω) depending on the material used, 100 ohms is the most common.

The cfficient of resistance is important for the measuring device which calculates the changes in temperature. The resistance value will relate to a temperature value, based on the increase in resistance (ohms) the TCR is used to determine the increase in temperature (ËšC).

Advantages of RTD Sensors

RTD sensors have many advantages.

·         Highly accurate

·         High repeatability

·         Consistent

·         Offer precise measurement even in extreme environments

·         Long term stability

·         Platinum RTD are suitable for higher temperature ranges

·         Most accurate and stable over time (when compared to thermocouples and thermistors)

Typical response time is between 0.5 to 5 seconds, which is not classed as an immediate response, but many applications will not necessarily require an immediate response which makes RTDs an ideal solution.  Many suitable industries for RTDs include; automotive, marine, white goods, HVACR and other industrial applications.

RTD Sensors from Variohm

We have a range of RTD sensors available, these offer different temperature ranges and are made of different materials. The links below give more information on individual products.

Thin film RTD Sensors – three different temperature ranges available; Cryo -196ËšC to +150ËšC, Medium -70ËšC to +500ËšC and High -70ËšC to +850ËšC.  

Nickel RTD Sensors – for -60 ËšC to +200 ËšC

Glass Wire Round RTD Sensors – particularly well suited to test and measurement applications

SMD Platinum RTD Sensors – for temperature ranges -50 ËšC to 150 ËšC

This is just a small part of the temperature range we have available here at Variohm. We offer products for a wide range of temperature measurement, control and compensation applications. We have over 40 years experience which enables us to meet the demanding industries of medical, aerospace, automotive, M applications, instrumentation, HVACR and motor control.