Zero Power Applications

The applications of thermistors, for the most part, are divided into two groups. This includes both zero power applications and self-heating applications. It is important to pick the correct application so that the thermistors work properly.

It is important to note that an NTC thermistor is meant for measuring temperature, and it is the main choice for measuring temperatures in a wide range. A thermistor can measure as low as -60 Celsius and can go as high as +300 Celsius. No single device can measure such a wide range, and so that is why you can find a wide array of different thermistors in styles and tolerances. Contacting a local company can help you make the correct decision when picking a thermistor.

It is rather common to find NTC thermistors paired with high-accuracy ohmmeters or Wheatstone Bridge Circuits. Calibrating the two devices must be done. This is done through picking the appropriate values for resistors R1, R2, and R3. Besides combining devices, you can do more to increase overall accuracy of measurements. For some functions, having extremely precise and consistent readings is a must.  By simply adding circuit elements, such as resistors and variable resistors, one can improve overall accuracy.

Utilizing a thermistor's measurements and controls can be done with off-the-shelf devices. One prime example would be a Datel Model PM Thermistor Input Intelligent Process Monitor/Controller.  This device will work with all standard inputs, and it is possible for the device to be used in a wide variety of temperature induction and control applications.

The thermistor is used to alarm users working with precise temperatures. The alarm applications are utilizing minimum electric circuitry.  Using a Wheatstone Bridge Circuit is one of the easier circuits to uses, and this is especially the case for a designer. In order for the alarm to be triggered, the indicating meter must be replaced with a relay (or any appropriate triggering device). The bridge must be balanced for a steady condition. If a bridge is unbalanced the steady state becomes rather inconsistent. The balance allows for a consistent flow across the relay.  When and if temperature changes, the bridge will become unbalanced, which would trigger the thermistor.

Navigating the world of thermistors can be difficult, so why not talk to a trained professional about your needs? Getting a wrong thermistor can lead to inaccurate temperature readouts, which would potentially harm your business. Shop smart when shopping for thermistors.

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