关键词: 七电极电导率传感器, 电路设计, 电导率测量

Abstract:

The fast and accurate conductivity measurement is of great significance in marine research and environmental protection.The article describes the basic principles and characteristics of the seven electrode conductivity sensor,and designs a fast measurement circuit with low temperature drift and high accuracy based on of the physical characteristics of the sensor itself as well as the requirements for high-precision measurement.D/A and A/D integrated circuit chips are used for precise sensor driving and high-speed sampling.The driving frequency and voltage are more accurate and easier to adjust than those of the traditional circuits,while the high-speed sampling avoids signal distortion in conditioning process.The effect of measurement is verified by experiments.

Key words: seven electrode conductivity sensor;circuit design;conductivity measurement