The Design And Research On Apparatus Of Cotton Moisture Measurement

The cotton moisture measurement is an important circle for the agency of cotton production,purchase,processing,storing and test. The cotton which has the higher moisture will affect strongly not only on the real weight of cotton and the physical and chemical performance of fibers, but also on the purchase,processing,storing,transportation and weaving, which could make big lost for our country. By now the extensively used cotton moisture measurement apparatus in china basically is the forepart resistance type. But this kind of apparatus also has the disadvantages ,such as it is not easy to operate,it is too large and the show of screen is not intuitive and so on. In the abroad, the similar products also has the disadvantages, such as it is too expensive,it is hard to maintenance and it is not easy to promotion and so on. Therefore it is all-important for us to design a steady performance,higher adjustability,more exact measurement and easy operating apparatus on cotton moisture measurement.After introducing the actuality and the advantages & disadvantages of the cotton moisture measurement apparatus at the present in detail, the paper put forward a new test system of cotton moisture measurement. The intelligence system makes up by the core of the 8 bit SCM PIC16C74 and sensor HM1520. The system has the merit of lower power waste,speediness,lower cost and smaller scale. The lower power waste and strong expanding function of SCM PIC16C74 is suitable to apply to the intelligence apparatus, and HM1520 (range: 0～20%, temperature scope:-30℃～+60℃) is suitable to apply to the lower measurement system, which is adapt to the cotton moisture (the normal cotton: 7%～11%) measurement.In this paper , we had completed the hardware and software of the moisture measurement system. Hardware circuit includes SCM PIC16C74 core circuit,lower moisture sensor HM1520 circuit,outer memorizer E2PROM circuit,series communication RS232C circuit,man—machine interface display and keyboard circuit,acoustic-optical alarm circuit and PMU circuit and so on.The paper completes the modularization design of the system's software. The software system can be divided into the following module :the main system module,data processing module,keyboard displaying and managing module,acoustic-optical alarm module and communication module and so on.It is the first time that the paper applies the PIC microchip into the cotton moisture measurement system.