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. 26, 1991
Filed:
Jun. 30, 1989
Applicant:
Inventors:
Thomas Yeh, South Weymouth, MA (US);
Joseph R Thibodeau, Dedham, MA (US);
Assignee:
Sigma Instruments, Inc., Weymouth, MA (US);
Primary Examiner:
Int. Cl.
CPC ...
H02H / ;
U.S. Cl.
CPC ...
361 59 ; 361 96 ;
Abstract
A faulted circuit indicator includes an inrush restraint circuit that suppresses a trip signal when an inrush current rises from below a minimum value to a trip value within a predetermined time and then drops again to another value such as the trip value. According to various aspects the restraint ends after a fixed time or after a variable time. According to another aspect a second trip circuit overrides the inrush restraint circuit when the current rises a given amount beyond the first trip value.