Fuji Electric Co., Ltd.

Hiromi Iwai

Hisaji Shinohara

Tatsuo Take

Shunichi Hatakeyama

Satoru Shiga

Masayuki Furusawa

Kazuro Shibata

Tsuneki Shinokura

Yoshihiro Tanabe

Nobuyuki Takao

Hiroshi Asaga

Masatoshi Nakajima

Katsuro Shiozaki

To provide a Cu-Cr alloy electrode material, a mixture of Cu and cr materials at a predetermined ratio is heated until the mixture has been entirely melted, and the molten metal obtained is quenched to precipitate fine Cr particles in a Cu base. Since Cr is melted into Cu before quenching, and then Cr precipitates, Cr particles finer than those in the sintering or infiltration method can disperse in a Cu base. This invention prevents defects such as voids in the structure and the weakening of the fusion of Cu and Cr or failure of Cr to precipitate into the Cu base caused by oxide films on the surface of the Cr particles, thereby providing a fine alloy structure.

Method for manufacturing electrode material for vacuum circuit breaker

A method of diagnosing the deterioration of a zinc oxide type lighting arrester having one or more series-connected non-linear resistance elements including steps of elimination of the effects of capacitive currents from phase currents; obtaining a synthesized waveform using a window type transformer based on the resistance elements alone; and diagnosing the presence of a deteriorated non-linear resistance element by generating a first pulse voltage when the maximum crest value of the synthesized waveforms exceeds a predetermined value, generating a second pulse voltage representative of terminal voltage of the resistance element, and calculating the difference between the first and second pulse voltages.

Method of diagnosing the deterioration of a zinc oxide type lightning

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Chiba, Japan

Hiromi Iwai