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. 24, 1985
Filed:
Mar. 01, 1984
Fumio Andow, Hachioji, JP;
Junichi Inagaki, Fuchu, JP;
Tokyo Shibaura Denki Kabushiki Kaisha, Kawasaki, JP;
Abstract
A protective relaying system in which the electric stations at both ends of a district of a power system to be protected optically transmit and receive reciprocally the information of the electric stations. A first protective relay device responds to both the electrical quantities from the opposite side terminal and electrical quantities of its own side terminal, and a second protective relay device responds only to the electrical quantities of its own side terminal. The respective protective relay devices are controlled by virtue of error detection circuits and signal discontinuity detection circuits connected to the optical transmission line to thereby discriminating the mere failure in the optical transmission line from the concurrent failures in both the optical transmission line and the transmission line so as to rapidly eliminate the failures.