Method for determining a conductivity, operating method of a magnetic-inductive flowmeter and magnetic-inductive flowmeter

US11841252B2 · kind B2 · utility

Inventors

• Helmut Brockhaus · Dinslaken, DE
• Markus Dabrowski · Duisburg, DE

Key dates

• Filing date: Mar 8, 2022
• Grant date: Dec 12, 2023
• Expiry date: Mar 8, 2042

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R27/22
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for determining conductivity of a medium includes: generating a signal with first and second frequencies; feeding the signal to first and second electrodes; determining a first voltage between the first and second electrodes, a first current through the medium for the first frequency, and a first impedance from the first voltage and first current; determining a second voltage between the first and second electrodes, a second current through the medium for the second frequency, and a second impedance from the second voltage and second current; determining and comparing phases of the first and second impedances; determining a medium resistance with a first formula when the first impedance phase is smaller than the second impedance phase; determining a medium resistance with a second formula when the first impedance phase is equal to or greater than the second impedance phase; and determining conductivity of the medium using the medium resistance.