RTD Overview


Resistance Temperature Detectors (RTD's) are stable and have a fairly wide temperature range, but are not as rugged and inexpensive as thermocouples. Since they require the use of electric current to make measurements, RTD's are subject to inaccuracies from self-heating.


An RTD capitalizes on the fact that the electrical resistance of a material changes as its temperature changes. RTD's rely on the resistance change in a metal. The resistance will rise more or less linearly with temperature.


Traditionally, RTD's use a length of conductor (platinum, nickel iron or copper) wound around an insulator. Newer styles use a thin film of the conductor deposited on a ceramic substrate.  RTD's are used to measure temperatures from -196° to 482° C (-320° to 900° F)



Sketch it, Build it!

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Sensor Products for our Process & Utility Customers

We have a broad selection of standard temperature sensors that are designed for general industrial use. From small

fast-response designs for engine testing, to 20’ long multi-point assemblies for reactors. If you can sketch it, we can probably build it!


• Heat recovery steam generator (HRSG)

• Boiler tubes

• Diesel engine

• Turbine/reactor temperature sensing

Heat Trace RTD's

When you choose our heat trace RTDs, you simplify installation and reduce your maintenance

expenses. Designed for use in any pipe or surface temperature measuring application, these sensors


  NEMA 4 or explosion-proof heads

  Heat transfer pad with excellent temperature response

  Rugged stainless steel sheaths for excellent mechanical


  Replaceable element design for simplified RTD replacement

   — to replace a faulty element, you simply remove the head

    cover, disconnect the leads and remove the flexible

    element.  You then insert the new element and reconnect

    the leads.

    Your process is up and running in minutes.

Options include dual RTD sensors, thermocouple sensors

   and a variety of weld pad and head styles

Gas Measurement Sensor

Can't find what you are looking for in our standard products? We would be happy to help you with a design to match your application!  Contact us today at 617.923.6966.


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Applied Sensor Technologies, a division of United Electric Controls, is a major manufacturer of thermocouple, RTD, thermistor and other temperature sensor assemblies. ISO 9001:2000 certified and a leading practitioner of JIT and Lean Manufacturing methods, Applied Sensor Technologies has expertise in a wide variety of process applications, from the blast furnace to the blast freezer; from chemical processing to food processing. Please visit our website: www.appliedsensortech.com, or give us a call at 617-923-6966!

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