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. 16, 1993
Filed:
Jun. 21, 1991
Paul Tripodi, Eybens, FR;
Merlin Gerin, Meylan, FR;
Abstract
To perform the long delay function of an electronic trip device, a quantity (TLR1) representative of the thermal current state varies proportionally to the difference (I.sup.2 -Is.sup.2) between the square of a value (I) representative of the current flowing in a conductor to be protected and the square of a current threshold (Is). This first quantity (TLR1) is used in combination with a second value (TLR2) to produce a tripping signal when the second value exceeds a preset value (TLR2max). The second quantity preferably increases proportionally to the square (I.sup.2) of the value representative of the current, when the first quantity exceeds a preset threshold (STLR1) and decreases, preferably exponentially, when the first quantity is lower than this threshold.