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. 05, 1988
Filed:
Feb. 10, 1986
Applicant:
Inventor:
Pierre Demeyer, Uriage, FR;
Assignee:
Merlin Gerin S.A., , FR;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02H / ;
U.S. Cl.
CPC ...
361 96 ; 364 50 ; 364483 ;
Abstract
Microprocessor-based digital solid-state trip unit (48) generating an inverse time long delay and/or short delay trip by digital simulation of the heating and cooling of a bimetallic strip. A digital value (TETALR), stored in a RAM memory simulates the temperature of the bimetallic strip, this value being incremented when the current exceeds a preset pick-up (ILR) or on the contrary decremented if the current is lower than this pick-up (ILR). Tripping is caused when the stored value (TETALR) exceeds a maximum pick-up (TETAMAX). The microprocessor (48) computes the incrementation factor (DTETAE) in terms of the square of the current.