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:
Jul. 05, 1983
Filed:
Jun. 11, 1982
Christian Cadet, Taverny, FR;
Bernard Dumortier, Montreuil sous Bois, FR;
Georges Souques, Paris, FR;
La Telemecanique Electrique, , FR;
Abstract
A protection device has first and second differential transformers each with a toroidal magnetic core through which pass the neutral and phase conductors of an alternating current distribution network, and a secondary winding. The secondary winding of the first transformer is coupled to the input of an amplifier followed by a rectifier, a threshold comparator and a control device adapted to release a circuit-breaker. The secondary winding of the second transformer is coupled to the output of the amplifier. The improvement is constituted by an auxiliary amplifier inserted between the output of the first amplifier and the terminals of the secondary winding of the second differential transformer.