Are resistance temperature detectors right for your application?

Resistance temperature detectors (RTDs) are slowly replacing thermocouples in many industrial applications below 600 degrees C as an effective way to measure temperature. That’s because these sensors offer many advantages.

Key features and benefits

RTDs are used to measure temperature by associating the resistance of the RTD element with temperature. Although thin film elements are most commonly used today, ceramic wire wound elements are a suitable choice when the temperature being measured is higher, or if there is vibration in the application.

The 100 ohm platinum element and the three-wire lead configuration are the most common for industrial temperature measurements, as the three-wire arrangement provides adequate compensation for leadwire resistance. For applications where high accuracy is required, however, the four-wire arrangement is an ideal choice because it fully eliminates all leadwire effects. They are typically 316 SS, ¼-inch diameter and are made in various terminations and configurations to suit the application.

Thanks to these many best-in-class features, there are many advantages to using RTDs. They offer high accuracy, low drift, excellent repeatability, long-term stability, and a wide operating range. Certain configurations can also be utilized in hazardous locations.

The caveat

Though there are many benefits to using this technology, there are also some disadvantages. RTDs are more expensive, less rugged, and are slower to respond to changes in temperature than thermocouples. In addition, if vibration is present, special construction is required. Manufacturers should weigh the pros and cons for their particular application and make an informed decision. Thermo-Kinetics can help.

A leading RTD manufacturer

As a leading manufacturer of process control and measurement equipment, Thermo-Kinetics can supply RTD probes and assemblies, as well as averaging RTDs. The company’s team of experts can help manufacturers determine whether resistance temperature detectors are right for their specific application. To learn more, contact Thermo-Kinetics today. 

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