電阻式土壤水分感測器之研究

Study on Electric Resistance Type of Soil Moisture Content Sensor

張敏德(Min-Te Chang) ； 黃裕益(Yu-I Huang) ； 盛中德(Chung-Teh Sheng)

《農林學報》 51卷1期 (2002/03) Pp. 15-27

https://doi.org/10.30089/JAF.200203.0002

摘要

本研究主要在探討自製電阻式土壤水分感測器輸出電壓值與土壤含水分的關係，並測試感測器在不同土壤含水分的反應性與穩定性，進而可達到土壤水分的有效管理。自製電阻式土壤水分感測器，採用特殊的高分子塑膠為母材，具有電阻式土壤水分感測器所需的微細連續氣泡性能，耐酸鹼、腐蝕、老化性及遇水分與濕氣不起水解作用等特性。實驗結果顯示電阻式土壤水分感測器在壤土質地中，土壤含水分10%~60%區間為其適用範圍，感測器輸出電壓值與土壤水分含量百分比為非線性反比例關係，適用範圍內感測器之輸出電壓變動率皆在0.31%以下。在土壤含水分10%、20%、30%、40%相間隔輸出電壓之差距於1.9933V~2.4733V之間，土壤含水分40%、50%之間感測器輸出電壓差距為1.238V，土壤含水分50%、60%之間感測器輸出電壓差距為0.7027V，皆有很明顯之區隔，易於控制應用。

關鍵字

電阻式 ； 土壤水分 ； 感測器

並列摘要

The objective of this study was to explore the soil moisture content sensor of electric resistance type, which was made by the researcher, their relationship between sensor voltage output and soil moisture content, and to test the responsive sensibility and the stability of the sensor in different soil moisture content. The developed sensor can be used to manage the soil moisture content effectively. The inventive absorptive electric resistance type of soil moisture content sensor was made of high-polymeric plastic. The sensor contented tremendous continuous micro pores to absorb moisture. The sensor also could tolerate pH、corrosion、aging and the resistance of hydrolysis due to moisture and humidity. The experimental results showed the developed sensor was suitable for the loam in the moisture content range from 10% to 60%. The relationship between output voltage and moisture content is inverse and non-linear. The variation percentage rate of output voltage is less 0.31%. The values of output voltages corresponding to the moisture levels of 10% 20% 30% and 40% were between 1.9933V and 2.4733V. The difference of output voltage between 40% and 50% was 1.238V and the difference between 50% and 60% was 0.7027V. These data of above are significant. In other words, the output voltage of developed sensor is sensitive enough to respond the moisture content change.

並列關鍵字

Electric resistance type ； Soil moisture content ； Sensor