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. 13, 2012
Filed:
Dec. 02, 2009
Yannick Maret, Wettingen, CH;
Daniel Schrag, Lufingen, CH;
Richard Bloch, Nussbaumen, CH;
Harald U. Mueller, Fulda, DE;
Yannick Maret, Wettingen, CH;
Daniel Schrag, Lufingen, CH;
Richard Bloch, Nussbaumen, CH;
Harald U. Mueller, Fulda, DE;
ABB Technology AG, Zurich, CH;
Abstract
A protective circuit arrangement is disclosed for electrical equipment supplied, for example, from a conductor loop in surroundings subject to explosion hazards in process engineering installations. To suppress current flow from an energy store of the electrical equipment into the conductor loop, an exemplary cascadeable switchgear cell is disclosed, having a first transistor, which allows the loop current to pass, and a second transistor, which short-circuits a parasitic base-emitter diode of the first transistor.