Thermistor, Model 103

Temperature Range 0-100°C
Accuracy ±0.2°C
Resolution at 0, 20. 70°C 0.01, 0.006, 0.001°C
Probe Length
Overall Length 37° ± 1°
Cable CAT-5
MicroLab Input Cat-5 Input A, B or C

The MicroLab Thermistor/Temperature Probe, Model 103, utilizes a negative temperature coefficient (NTC) thermistor housed in a closed, stainless steel shaft to provide quick and accurate temperature readings.  This an industrial grade temperature sensor mounted in a 1/16 inch diameter stainless steel tube (half the diameter and roughly 1/3 the thermal mass of common educational thermistors). This gives low thermal mass and fast response.

The sealed, electrically isolated stainless steel enclosure provides fast response and allows temperature data to be recorded concurrently with pH, REDOX, conductivity, or other electrochemistry measurements without affecting the sensor behavior.  Its high resolution and low noise allow you to monitor small temperature changes.

The Thermistor/Temperature Probe, Model 103, like all NTC thermistors, decreases in resistance as temperature increases.  The MicroLab Interface, Model FS-528, measures this resistance by applying a precisely measured voltage, measuring returned current, and applying Ohm’s Law ( R = V/I) to calculate resistance.   One can, if desired, display this resistance to explore the temperature/resistance response of the sensor.  MicroLab’s Model FS-528 lab interface has 16 bit precision, which allows for an extra decimal of precision in temperature measurements compared to 12 bit lab interface devices. This means you can use smaller sample sizes with the same accuracy and precision you would get from 12 bit devices requiring larger samples.

The Thermistor/Temperature Probe, Model 103, is equipped to work most effectively with the MicroLab Interfaces.  MicroLab software utilizes the Steinhart-Hart equation to calculate the temperature of the thermistor, a technique used throughout industry and in research labs.

Thermistors can be oven dried at 100°C, but should never be placed in a flame. Placing the tip in a flame will damage any thermistor.  In colligative experiments such as freezing point lowering, a dry probe will give the best results. Even a trace amount of moisture in a small scale experiment can add sufficient water (as a solute) to change the freezing point dramatically.