Tokyo Shibaura Denki Kabushiki Kaisha

Toshikazu Satoh

Susumu Nishiwaki

Satoru Yanabu

Mizuho Yamashita

Yoichi Murakami

Susumu Imai

An arrester having at least two stacks of non-linear resistors connected in series, an arcing gap device connected to shunt one stack of resistors when the gap means sparks over, and a hermetically sealed housing enclosing the resistor stacks and arcing gap device and filled with sulfur hexafluoride gas having a gauge pressure not less than 2 kg/cm.sup.2. The impedance of the one resistor stack is from about 15% to about 35% of the total impedance of the two resistor stacks when the arcing gap means sparks over, and the rated voltage of the arrester is not less than about 50 KV.

Lightning arrester

A lightning arrestor comprising at least two stacks of resistor disks juxtaposed within a housing and electrically connected in parallel. The stacks include the same number of disks, at least 35, and preferably 100 or more. Each stack comprises at least two sub-stacks which are aligned end-to-end and electrically connected. Adjacent sub-stacks of parallel stacks are mechanically connected but electrically insulated from each other.

A series circuit of a gap section and a valve block is connected between a transmission line and the ground. The valve block consists of a plurality of nonlinear resistor elements connected in series. A first impedance circuit consisting of a resistor and a capacitor connected in series is connected in parallel to the gap section. Also, a second impedance circuit consisting of another resistor and another capacitor connected in parallel is connected in parallel to the valve block. The ratio of the voltage applied across the gap section to that applied across the valve block is determined by the ratio of the impedance of the first impedance circuit to that of the second impedance circuit. A pair of discharge electrodes included in the gap section, which are a prescribed distance apart from each other, comprise a narrower gap region at which spark is started.

An arrester comprises a plurality of blocks connected in parallel between first and second connecting metal plates and each comprised of a plurality of stacked nonlinear resistor elements, at least one block comprised of a plurality of stacked nonlinear resistor elements and connected between the second connecting metal plate and a third connecting metal plate grounded, and a discharge gap connected in parallel with the later-mentioned block and between the second and third connecting metal plates. The discharge gap is provided below one of the blocks connected in parallel between the first and second connecting metal plates.

Growing community of inventors

Yokohama, Japan

Toshikazu Satoh