Wide dynamic range conductivity measurements in water

摘要

A conductivity meter for measuring the conductivity of a fluid is provided. The conductivity meter has a cell circuit and a control unit circuit. The cell circuit has a square wave drive amp, a cell, and a trans-impedance amplifier. The fluid flows through the cell. The control unit circuit and the square wave drive amp are configured to apply a square wave pulse train having a voltage to the fluid of the cell, thereby inducing a flow of current through the fluid in the cell. The cell circuit trans-impedance amplifier and the control unit circuit are configured to obtain a plurality of measurements of current flowing through the fluid in the cell and estimate a raw conductivity of the fluid in the cell using the current flow measurements. A method for measuring the conductivity of a fluid is also provided.

主权项

1. A conductivity meter for measuring the conductivity of a fluid comprising:
a cell circuit and a control unit circuit; said cell circuit comprising a square wave drive amp, a cell, and a trans-impedance amplifier; wherein said fluid flows through said cell; wherein said control unit circuit and said square wave drive amp are configured to apply a square wave pulse train having a voltage to the fluid of said cell, thereby inducing a flow of current through said fluid in said cell; wherein said cell circuit trans-impedance amplifier and said control unit circuit are configured to obtain a plurality of measurements of current flowing through said fluid in said cell and estimate a raw conductivity of said fluid in said cell using said current flow measurements; wherein said control unit circuit estimates the raw conductivity value of said fluid in said cell by fitting said current flow measurements to a double exponent decay function.