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. 20, 2001
Filed:
Apr. 30, 1999
Lewis W. Kenyon, Blacksburg, VA (US);
Isaac L. Flory, IV, Blacksburg, VA (US);
Hubbell Incorporated, Orange, CT (US);
Abstract
A method and apparatus are provided to retrofit a gas discharge lamp ballast designed for use with a first lamp having a first power rating to be used with a second lamp having a second power rating. The ballast has a core, a coil and a serially-connected ballast capacitance device and is characterized by a first net impedance of the ballast reactance to allow operation of the first lamp in an operating range in which the first lamp is designed to operate. When the first lamp is replaced with a second lamp having a different lamp impedance than the first lamp, the capacitance of the ballast capacitance device is selected so as to change the first net impedance of the ballast to a second net impedance which allows the ballast to maintain proper operation of the second lamp in accordance with its specifications and rating.