Method and apparatus for detecting faults in a structure by measuring voltage drop between surface points thereof

US4683419A · kind A · utility

Assignee

• Interatom GMBH · DE

Inventors

• Rolf Neuelmann · Bensberg, DE
• Manfred Fortmann · Much, DE

Key dates

• Filing date: Sep 20, 1985
• Grant date: Jul 28, 1987
• Expiry date: Sep 20, 2005

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N27/20
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for monitoring structures by measuring electrical quantities including subjecting an electrically conducting component to an a-c current with a predetermined frequency in a given direction generating a magnetic flux in a given direction, tapping a voltage drop across two measurement points mutually spaced apart by a given distance at individual partial regions of the component with two measuring lines contacting the component, forming a first conductor loop from the measuring lines and the component with an inductively effective area being as small as possible, forming a second conductor loop being substantially parallel to the given direction of the current and perpendicular to the given direction of the magnetic flux, tapping an induction voltage from the change of the magnetic flux as close as possible to the measuring points with the second conductor loop, feeding the voltage drop and the induction voltage to an electronic evaluation circuit, and deriving the local resistance of the component at the measurement points from the voltage drop and the induction voltage with the evaluation circuit and an apparatus for carrying out the method.