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:
Apr. 20, 1999
Filed:
Feb. 26, 1998
Thomas Christopher Rae, Irwin, PA (US);
Thomas Edward Natili, Cabot, PA (US);
Robert Tracy Elms, Monroeville, PA (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
An arc fault detector of the type which generates a trip signal when a time attenuated accumulation of pulses produced each time an arc is struck reaches a selected value, includes a pulse conditioner which discriminates against false trips induced by phenomena such as tungsten bulb burn out and turn on of a cold tungsten bulb controlled by a dimmer. The pulse conditioner includes a zener diode which limits the amplitude of the pulses applied to the integrator, and stretches all of the pulses to reduce the variation in pulse duration. The latter can be accomplished by a peak detector which stretches pulses which reach the zener limit to a duration of at least about a half cycle.