Patent ID: 9651511
Date: 2017-05-16
CPC Classifications: G01N

Claim:
1. A conductivity sensor comprising: a housing defining a flow conduit for the passage of a fluid; first and second electrodes spaced apart along said flow conduit; excitation circuitry operable to connect to said electrodes and operable to generate excitation signals; and processing circuitry operable to connect to said electrodes and operable to determine conductivity measurements of fluid flowing through the housing; wherein said excitation circuitry is operable to apply first and second excitation signals having first and second excitation frequencies respectively, to at least one of said electrodes; and wherein said measurements include a desired component that varies proportionally with the conductivity to be measured and an undesired component that varies with polarisation effects of the electrodes and wherein the processing circuitry is operable to use the measurements obtained for the first and second frequencies to determine a correction to be applied to said conductivity measurements for correcting for the polarisation effects of the electrodes.