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:
Sep. 09, 2003
Filed:
Jan. 29, 2001
Applicant:
Inventors:
Ulrich Baumgaertl, Berlin, DE;
Wolfgang Röhl, Berlin, DE;
Holger Hochgraef, Ganzer/Wusterhausen, DE;
Assignee:
Siemens Aktiengesellschaft, Munich, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R 3/108 ;
U.S. Cl.
CPC ...
G01R 3/108 ;
Abstract
A method and circuit arrangement for measuring a current are described, which can be used in electrical engineering to precisely trigger electronic tripping devices in circuit breakers. The current is measured according to magnitude and phase in such a way that only the fundamental wave of the current between precisely determined current zero crossings is sampled at a low sampling rate, and the root mean square is calculated on the basis of the measured phase angle and amplitude. The exact phase angle is measured using a conventional PLL circuit with a downstream zero switch.