The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 27, 2013
Filed:
Dec. 12, 2008
Changlin Wang, Shanghai, CN;
Changlin Wang, Shanghai, CN;
Mettler-Toledo AG, Greifense, CH;
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 fthrough 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 R; then exciting the electrodes with a rectangular shaped, alternating current of another frequency fthrough 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 R. Based on a mathematical model, a relation between the resistance R between the electrodes to be measured and the first and second impedances Rand R, and the ratio n of the frequency fto fis established, so as to derive the resistance R between the electrodes. The conductivity of the solution can be derived by incorporating an electrode constant.