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:
Oct. 16, 1984
Filed:
Jul. 08, 1982
Keizo Nakayama, Hitachi, JP;
Kazuo Seo, Tohkai, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Transmission lines have both their terminals connected with bus lines through breakers, respectively, and connected to earth through earth switches, respectively. Protecting relay devices are fed with not only the outputs of voltage transformers and current transformers but also the contact signals made coactive with the breakers and earth switches at the terminals considered. Those contact signals are transmitted through signal transmission devices to the other terminals, and the contact signals of the breakers and earth switches at the other terminals are transmitted. The protecting relay devices detect the fault of the transmission lines, if any, to trip the breakers and to confirm the open states of the breakers from the breaker contact signals of the terminals considered and the other terminals thereby to close the earth switches. These earth switches are opened after a suitable time period to confirm the open states thereof from their contact signals at the terminals considered and the other terminals thereby to reclose the breakers.