Abstract: In a differential-type protective relay actuated to generate a signal necessary for the protection of a bus of an electric power system when a troubled current has flown through the bus, a gapped first transformer is used to receive an output from a current transformer which is adapted to detect each current in the bus. Each output of a first detection element, which is actuated when the output of the first transformer is higher than a preset level, is fed out to the exterior only when a value obtained by subtracting the sum of the maximum of the output of the first transformer and the value of a signal obtained by shifting the phase of the output through a predetermined angle from the value of a signal obtained by subjecting the output of the first transformer to full-wave transformation is equal to or lower than a preset value.

Abstract: A cell composed of an anode with a light metal as an active material, a cathode with manganese dioxide as an active material, and an organic electrolyte. The cathode contains an alkaline earth metal oxide. The cell is superior in storage with the swelling of the cell and the increase of the cell impedance is little during the preservation.

Abstract: This invention relates to improvement in an organic electrolyte battery employing a light metal as an anodic material; organic electrolyte; and CuO as a cathodic material.By using, as the cathodic material, the solid solution of alkali metal oxide and CuO as a mother substance, the delivered volumetric energy density of the battery is fairly increased.