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:
Jan. 03, 1989
Filed:
Aug. 24, 1987
Applicant:
Inventor:
Glenn W Swift, Winnipeg, CA;
Assignee:
Federal Pioneer Limited, Toronto, CA;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02H / ;
U.S. Cl.
CPC ...
361 42 ; 361 93 ;
Abstract
A ground fault detector for an AC circuit is responsive to resistive ground fault current but not to capacitive ground fault current. Current in the AC circuit is sensed and a corresponding signal current is produced. The direction of the signal current is reversed in each alternate half AC cycle without reversing the signal current in each intervening half cycle, the unreversed and the reversed signal current is averaged, and the presence of averaged signal current above a predetermined value is sensed to indicate significant resistive ground fault current.