Properties of a NTC Thermistor

NTC thermistors are used in a wide range of applications throughout many different industries. When determining the appropriate thermistor for a desired application, it is important to consider the thermal and electrical properties of this device. When you don't, desired applications become hard to achieve. These properties govern the geometry of the NTC thermistor when they are applied to other devices. Reading a company’s product catalog can be confusing at times. Thermal and electrical properties are broken down into a few categories that are found on a catalogue. This includes: thermal time constant values, resistance as temperature, and nominal resistance values. A manufacture of thermistors will be able to provide further details and explanations about their products, so if you have any questions just call. Below we will be going over the properties of these devices.


NTC thermistors are usable when they meet three simple electrical characteristics. These three things are:

Current-time- a device that is self-heated has a temperature rise that is a function of time. Thermistors have a low resistance, and so the current change will start off low. When self-heating goes up, current change will increase. This will also for a low rate of resistance. Current time is utilized when working with time delays, filament protections, and surge suppression.

Resistance temperature- there is general categories that are associated with this characteristic. This includes: the compensation of temperature, the control of temperature, as well as resistance thermometry.

Voltage current- several applications rely on this characteristic. One type of application is when there is a varied dissipation that should be constant. Another is when the parameters of an electrical current are not consistent. This is usually caused by a change in source resistance. The characteristics of the thermistor also help to deal with ambient temperature that has no consistency.

There are specified mathematical equations that are used to calculate the appropriate properties of a desired NTC thermistor. For each of the three above characteristics, there are several equations that allow for the perfect devices to be purchased. Rather than figuring out all this information alone, call a manufacture that can help you work through your application problems. By making the wrong calculations you will only be wasting time and money. Sometimes it might seem as if there is too much information to navigate alone, but you aren't alone. Reaching out to professionals will ensure you get exactly what you need.

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