Temperature-compensated electromagnetic flowmeter

US4236410A · kind A · utility

Assignee

• Fischer & Porter GmbH · US

Inventors

• Eggert Appel · Dransfeld, DE
• Gottfried Geisler
• Wilfried Kiene · Menden, DE
• Peter Neal Nissen · Frederikssund, DK

Key dates

• Filing date: Nov 2, 1978
• Grant date: Dec 2, 1980
• Expiry date: Nov 2, 1998

Classification

• Technology area (CPC G): Physics
• CPC primary: G01F1/60
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An electromagnetic flowmeter in which the fluid to be metered is conducted through a flow tube provided with a pair of diametrically-opposed electrodes. The fluid intercepts a magnetic field established in the flow tube by a magnetizable core having a coil wound thereon through which an excitation current flows, thereby inducing a signal voltage in the electrodes. Because the permeability of the core is temperature-dependent, changes in temperature affect the strength of the magnetic field and adversely influence the signal voltage. Compensation means are provided to render the signal voltage independent of temperature, thereby producing an output signal accurately proportional to flow rate.