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:
Mar. 27, 1997
Eddy So, Gloucester, CA;
David A Bennett, Smiths Falls, CA;
National Research Council of Canada, Ottawa, CA;
Abstract
A current ratio device for use in forming a hand-held openable-core clamp-on type of current transformer. The device employs electronically-aided three-stage circuitry for forming a current transformer capable of accurate low current measurements over a wide range of operation. Such a current transformer is specifically adapted for use with highly accurate active/reactive power and energy meters, and harmonic power analysers. For example a preferred form of clamp-on transformer can be used to measure currents in the range from 1 A to 200 A with ratio errors of less than 50.times.10.sup.-6 for both the in-phase and quadrature components.