In order to choose the best thermistor for your application, you will need to consider the following aspects of each thermistor type.
We can begin with the basics. Start with the device size and the desired physical characteristics of the thermistor that you need. Next, think about exactly what the NTC thermistor that you are looking for needs to do. Now, consider the resistance temperature curves that you are looking for. Most manufacturers of NTC thermistors will have various tables available of resistance ratios for their products that you can look at. Each material system will also have its own limitations regarding the range of nominal resistance values available that will work.You should also consider the resistance tolerance for the NTC thermistors.The most cost efficient thermistor will have the comprehensive tolerance. Beta tolerance and resistance limits must also be considered when selecting your thermistor, as this fixes your lowest and highest resistance values.
Depending on the desired use for the thermistor, you may also want to consider the issues of curve matching and the interchangeability of the thermistor. Cost and performance may need to be considered when you are looking these factors. You may want to think about metalized surface contact thermistors and those hermetically glass enclosed when considering these elements.
Finally, calibration is something to consider when looking for the right thermistor type. Luckily, there are NTC thermistors available with precise calibrations that offer both broad tolerance and low cost. Testing and calibration of NTC thermistors can be very tricky, so be sure to find out how the calibration and testing of the thermistor is handled before you make your purchase.