A versatile computer controlled measuring system for recording voltage-current characteristics of various resistance sensors

Abstract

Abstract A computer controlled measuring system for generating the static voltage versus current (V-I) characteristics of various resistance sensors is described. Based on the measured data, the dissipation constant of sensors can be calculated The software enables experiments with several types of resistance sensors having current controlled V-I characteristics to be performed. Experiments were carried out with negative temperature coefficient (NTC) thermistors, metal wire and metal film anemometer sensors, as well as with the positive temperature coefficient (PTC) silicon temperature sensors. The computer-controlled system makes possible the precise generation of the individual static V-I characteristics of a sensor in relatively short duration experiments, without the necessity of knowing the sensor time constant. The eventual damage to a sensor during the test, which frequently occurs in manually controlled measurements, is prevented by appropriate software solutions. By studying the V-I characteristics of PTC silicon temperature sensors at various air speeds it has been shown that these sensors are potentially very suitable for air speed measurements, in which high sensitivity, robustness and relatively slow time response is desirable.