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:
Dec. 02, 1986
Filed:
Mar. 19, 1984
John D Ainsworth, Stafford, GB;
Abstract
A D.C. current transformer (used for measuring D.C.) comprising a common primary winding and a pair of saturable magnetic cores on which respective secondary windings are wound and connected in opposite series in series to a source of alternating e.m.f., is provided with phase-sensitive device for determining the sense of the unknown D.C. in the primary winding. The phase sensitive device periodically senses and integrates the voltage (whose waveform is the -45.degree. to +45.degree. portion of a sine wave) across at least one of the secondary windings. The sense of the integrated waveform depends on whether said voltage is initially positive or negative, and is determined by the sense of the unknown D.C. in the primary winding. Preferably said voltage is sensed at each half cycle of said alternating e.m.f.