Method and device for measuring the electrical conductivity and/or resistivity of a solution
US8521442B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 12, 2008 |
| Grant date | Aug 27, 2013 |
| Priority date | — |
| Expiry date | Jun 14, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/06
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An exemplary method for measuring the electrical resistance and/or electrical conductivity of solutions, includes: exciting the electrodes with a rectangular shaped, alternating current of a certain frequency fH through a connecting cable; synchronously rectifying a voltage of the electrodes of the measuring cell in response to the alternating current, calculating a first average voltage, dividing the first average voltage by the current amplitude to obtain a first impedance RH; then exciting the electrodes with a rectangular shaped, alternating current of another frequency fL through the connecting cable; synchronously rectifying the voltage of the electrodes in response to the alternating current, calculating a second average voltage, and dividing the second average voltage by the current amplitude to obtain a second impedance RL. Based on a mathematical model, a relation between the resistance R between the electrodes to be measured and the first and second impedances RH and RL, and the ratio n of the frequency fH to fL is established, so as to derive the resistance R between the electrodes. The conductivity of the solution can be derived by incorporating an electrode constant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.