The NTC (negative temperature coefficient) thermistor precision is significantly increased by the calibration process. The full calibration procedure process itself is sophisticated as it requires a set of calibration points when using the Steinhart-Hart equation for the linearization of the T(R) (Temperature -Resistance) characteristics. Aging and degradation processes tend to distort the metrological characteristics of the NTC thermistors. The novel method of calibration for groups of thermistors produced by the same manufacturer using the same technology is proposed in this paper. The initial calibration data acquired from the calibration results or from the manufacturer is used for approximate computations. During the additional calibration, the approximate data for the group of thermistors is adjusted using linear transformations. The result analysis for five different types of thermistors (A, B, C, D and E) revealed that the temperature measurement errors in the temperature range from 20 0 C to 80 0 C can be reduced by up to 10 times using the proposed method. The aging and degradation processes were investigated using the thermocycling procedure implemented with steep transitions (100 0 C ... 0 0 C ... 100 0 C). The thermistor R(T) characteristics were repeatedly measured after 1000, 2000 and 3000 thermocycles. The results revealed that statistically, the average error of the temperature measurement for the types C, D and E increased significantly after 3000 thermocycles, whereas the measurement error trend of the thermistors of types A and B was insignificant (p > 0.05).
The parameters represented on manufacturer datasheet are usually insufficient for the optimum selection of thermistors. Some manufacturers give generalized numerical data of R(T) dependences. Using this data it is possible to select successfully the most suitable thermistor and equation for describing of T(R) dependence. It is shown that by selecting four points in the generalized characteristic it is possible to calculate the coefficients of the approximation equation. By the application of these coefficients in the calculations the temperature measurement errors can be decreased by an order. The results of calculations and experiment are given. Ill. 4, bibl. 8, tabl. 5 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.111.5.357
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.