Magnetic flowmeter with fault detection

US5370000A · kind A · utility

Assignee

• Fischer & Porter GmbH · US

Inventors

• Jorg Herwig · Dransfeld, DE
• Dieter Keese · Uslar, DE
• Karl-Heinz Rackebrandt · Dransfeld, DE
• Hans-Werner Schwiderski · Nörten-Hardenberg, DE

Key dates

• Filing date: Jun 30, 1992
• Grant date: Dec 6, 1994
• Expiry date: Jun 30, 2012

Classification

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

Abstract

A circuit for detecting faults in a magmeter system in which an electrically conductive fluid flows which is maintained at a reference potential. The circuit includes at least two electrodes in contact with the fluid. The electrode signals are conducted to the corresponding inputs of a measuring circuit. An alarm circuit is connected ahead of the measuring circuit. A difference in the magnitude of the values (+U.sub.S and -U.sub.S) of the electrode signals and/or non-symmetries in the noise content of the electrode signals and/or a disturbance in the high frequency signal (U.sub.G) in a loop which contains the electrodes and a high frequency producing generator causes an alarm to be activated.