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:
May. 06, 2003
Filed:
Dec. 04, 2001
Ulrich Baumgaertl, Berlin, DE;
Manfred Schiller, Berlin, DE;
Siemens Aktiengesellschaft, Munich, DE;
Abstract
In power circuit breakers including a current transformer with a current detection coil without any iron and including an integration circuit connected downstream from the current detection coil, the unavoidable time constant of the integration circuit can lead to spurious trappings. This is avoided by a method in which the instantaneous values of the current are detected and stored at defined periodic intervals. The stored measured values are compared on the basis of polarity and magnitude. If it is found that the stored values have the same polarity and fall monotonally, it is assumed that the DC element is originating from the integrator and a tripping inhibit signal is set in the electronic release of the power circuit breaker.