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:
Oct. 29, 2013
Filed:
Mar. 11, 2011
Hugh T. Kinsel, Sugar Hill, GA (US);
Joselito Endozo, Dacula, GA (US);
Hugh T. Kinsel, Sugar Hill, GA (US);
Joselito Endozo, Dacula, GA (US);
Siemens Industry, Inc., Alpharetta, GA (US);
Abstract
An apparatus and method for a supervisory circuit for a ground fault detection device or ground fault circuit interrupt (GFCI) device is disclosed in which is a test stimulus signal for a self test of the GFCI device is generated on a second secondary winding on a toroid of a differential current transformer. The GFCI device includes line and neutral conductors configured to connect an AC power source and a load. A differential current transformer includes a toroid, through which the line and neutral conductors pass, a first secondary winding wound on the toroid to generate a current in response to an imbalance of magnetic flux in the toroid, and a second secondary winding wound on the toroid. A differential ground fault detector is electrically connected to the first secondary winding of the differential current transformer to compare current generated in the secondary winding to a trip threshold. A controller is configured to control a test stimulus signal to be generated in the second secondary winding wound on the toroid of the differential current transformer.