Choosing Correct Thermistors

Thermistors are temperature-sensing tools that are sintered semiconductors. The device shows small changes in temperature based on large changes in resistance. Thermistors are made from a mixture of different metals and metal oxides. After the materials are mixed, the thermistor is formed to its required shape. Shaped can be customized and coating can be added to make form bead-style thermistors.Thermistors

There are two types of coating that are possible for thermistors, and this includes epoxy and glass. A glass coating is for high temperature applications. The normal range of temperature is -58 through 572 degrees Fahrenheit. Epoxy coating are the counter-point of glass, so it works best with low temperature.  Despite the difference between coatings, they are used to mechanically protect the thermistor and wire connections. The coating also protects against corrosion and humidity.

Base resistance is important for a thermistor's performance. The rule of thumb is that the lower the temperature the lower the resistance needed. For applications lower than 70 degrees Celsius, resistance should be set between 2252 and 10,000Ω. Temperatures that exceed 70 degrees will require a resistance of 10,000Ω or higher. Determining the appropriate resistance is important for making accurate temperature readings.

When picking thermistors, three things need to be considered above all other things.

First, the base resistance must be found.

Second, the relationship between resistance and temperature must be set.

Lastly, the thermistor size and package style is picked.

Do not make these decisions alone. Reach out to professionals for more answers.

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Thermistors