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:
Jan. 26, 1988
Filed:
Feb. 27, 1986
Hitachi Cable, Ltd., Tokyo, JP;
Abstract
A method for diagnosing an insulation deterioration of a power cable comprising a step of measuring a DC current component in the AC voltage applied to said power cable, by using a filter circuit for cutting off an AC current and a DC current measuring apparatus for measuring small magnitude of DC current. According to the present invention, said filter circuit and said DC current measuring apparatus are joined in parallel each other and connected between a power source and one end portion of said power cable to be diagnosed. The DC current measuring apparatus can detect the polarity, magnitude, and time lapse characteristics of said DC current component for analyzing and estimating the insulation deterioration.