The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 08, 2005
Filed:
Feb. 28, 2003
Jens Titschert, Lunen, DE;
Emmanuel Charruau, Lunen, DE;
Helmut Hermann, Bochum, DE;
DBT Automation GmbH, Lunen, DE;
Abstract
A method and a circuit arrangement () for the measurement of earth leakage in intrinsically safe current feeds to electronic control units () for underground mining installations and machines, whereby at least one earthed control unit is connected to the two intrinsically safe potentials of an intrinsically safe direct current supply () and at least one earth leakage sensor () is provided for earth leakage measurement with which steps of the periodical application of a test potential (U) from an intrinsically safe switchable test voltage source () to an RC-element (), isolated from earth () by means of decoupling capacitors (C, C), measurement of the charging or discharging current behaviour of the RC-element () after each switching of the test voltage source () and comparison of the measured charging or discharging behaviour with stored reference data.