Apparatus and method for the measurement of electrical conductivity and dielectric constant of high impedance fluids
US8552750B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 29, 2010 |
| Grant date | Oct 8, 2013 |
| Priority date | — |
| Expiry date | Aug 5, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R27/2647
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensor, a system of direct measurement using that sensor, and a method of direct and simultaneous measurement of conductivity and dielectric constant of a fluid, particularly high impedance, hydrocarbon-based fluids. The sensor has a cell that holds the fluids to be measured between a single pair of coaxial, bare metal electrodes connected through interface circuitry to measurement circuitry preferably implemented in one or several IC's. The sensor has a mutually compatible electrode geometry that provides both the correct cell constant for measurement of conductivity of hydrocarbons fluids (typical range 0-100,000 pS/cm), and a bulk capacitance (for use in dielectric constant measurement) in the range of measure of readily available low cost commercial IC's (having a typical capacitance measurement span of <10 pF, with a total bulk capacitance at the chip of <20 pF). The cell conductivity constant for use with hydrocarbon-based oils having a conductivity in the range of 1 to 500,000 pS/M is preferably less than or equal to about 0.1. The cell bulk capacitance with hydrocarbon fluids inside the sensor results in a bulk capacitance of at least about 4 pF. In one embodiment, the el…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.