Moisture tester for grain and oil crops

Abstract

The present invention discloses a grain, oil and water testing apparatus comprising a test start-up circuit, a microprocessor, a temperature measuring circuit, a display circuit, a buzzer, a boost and voltage stabilizing circuit, and a measured signal processing circuit, wherein said boost and voltage stabilizing circuit comprises a boost circuit, two groups of dividing voltage circuits and a selection control circuit. In a relevant testing range, the testing voltage does not depend on samples to be tested, then the consistency and veracity of the testing are ensured. The setting of the selection control circuit enables the dividing voltage values of the dividing voltage circuits to keep stable by a dynamic control of the boost circuit, and then improves the testing veracity of said testing apparatus. Field-effect transistors and precise resistors form four groups of dividing voltage circuits which can be selected under the control of the microprocessor, according to resistance values of samples to be tested, to ensure the testing accuracy by limiting output voltage within an appropriate range.

Description

technical field [0001] The invention relates to a measuring instrument, in particular to a grain and oil moisture tester, which belongs to the technical field of analytical instruments. Background technique [0002] Among the methods used to detect the water content of commercial grain and oil, non-standard testing methods usually adopt the capacitance method and resistance method. The capacitance method uses grain as the medium of the capacitor for measurement; the resistance method also uses grain as the resistance Measurement, because the electrode is generally separated from the body, it is very inconvenient to use, and because its measurement range is relatively narrow, it can only be used for the determination of constant moisture. The error is relatively large and cannot provide accurate and reliable data, so it has great limitations in use. The standard measurement methods include "fixed temperature and timing drying method", "tunnel oven method" and "twice drying m...

AI Technical Summary

Problems solved by technology

[0002] Among the methods used to detect the water content of commercial grain and oil, non-standard testing methods usually adopt the capacitance method and resistance method. The capacitance method uses grain as the medium of the capacitor for measurement; the resistance method also uses grain as the resistance Measurement, because the electrode is generally separated from the body, it is very inconvenient to use, and because its measurement range is relatively narrow, it can only be used for the determination of constant moisture. The error is relatively large and cannot provide accurate and reliable data, so it has great limitations in use

The standard measurement methods include "fixed temperature and timing drying method", "tunnel oven method" and "twice drying method". Although the results obtained by these measurement methods are relatively accurate and reliable, the disadvantage is that the workload is large and the procedure is complicated. , time consuming

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