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:
Nov. 12, 1996
Filed:
Mar. 10, 1995
David A Vosika, Salem, VA (US);
Robert S Feldstein, Dobbs Ferry, NY (US);
Hubbell Incorporated, Orange, CT (US);
Abstract
A self-diagnostic circuit for an emergency lamphead is disclosed that is effective during standby operation of the lamphead to indicate whether the lamphead is capable of operating in an emergency mode. The self-diagnostic circuit includes a high-impedance circuit path connected in series with the lamphead and including an indicator, such as an LED, which is energized by a battery current passing through the circuit path and lamphead during the standby mode operation. The battery current is insufficient to illuminate the lamphead, but is sufficient to energize the LED whenever proper electrical continuity exists through the lamphead. A second high-impedance circuit path may be connected in parallel with the lamphead, in order to energize a second LED when proper continuity does not through the lamphead. The self-diagnostic circuit may be incorporated into each of a plurality of remote lampheads in a multiple-lamphead system, and may include a bipolar transistor or FET for isolating the self-diagnostic circuits of the lampheads from each other.