Abstract: A spark gap includes two terminal electrodes enveloping a cavity. The cavity includes an electrical discharge space between the two terminal electrodes. The spark gap also includes an electrical insulator between the two terminal electrodes.

Abstract: A spark gap (1; 21; 50) is indicated with a cavity (3; 23; 43), which is enveloped by two terminal electrodes (7a, 7b; 27a, 27b; 47a 47b) having an electrical insulator (2; 22; 42) placed therebetween, and with a rod electrode (4; 24; 44), which projects into a tubular electrode (5; 25; 45). Provided in one implementation are recesses (11; 41) of the terminal electrodes on the side of the cavity (3; 43) and a guidance of the terminal electrodes on the inside wall of the insulator. In another implementation, reinforcement electrodes (12a, 12b; 27c, 27d) are provided, which are connected to one of the terminal electrodes. The two implementations can be combined.

Abstract: A gas-filled surge arrester includes at least two electrodes, a hydrogen-containing gas filling and an activating compound applied to at least one of the electrodes. In order to ensure the required operating behavior of the surge arrester even at temperatures to 40%, the activating compound contains nickel powder in an amount of 30 to 35% by weight and potassium silicate in an amount of 25 to 30% by weight as basic components, sodium bromide in an amount of 15 to 20% by weight, as well as aluminum powder, sodium silicate and barium titanate as further components each in an amount of 5 to 10% by weight.

Abstract: A module is provided which includes two gas-filled surge arresters arranged next to one another in a housing. An auxiliary discharge gap and a short-circuit device is associated with each surge arrester. One side of each surge arrester is in contact with a plate, which forms the ground, as well as the stationary electrode of the short-circuit device. On the other side, the plate is in contact with two varistors which form the auxiliary discharge gaps. A cap, forming the movable electrode of the spring-loaded short-circuit device is placed on each varistor with a meltable spacer between them.

Abstract: A gas-filled overvoltage arrester with an electrode activation compound. In order to ensure a high degree of adherence of the activation compound to the electrodes in a gas-filled hydrogen-containing overvoltage arrester, the activation compound comprises a first aluminum component, a second halide component, and a third dielectric or ferroelectric metal oxide component. These three components are present in the proportions of 50 to 70, 20 to 40, and 3 to 10 mol. %, respectively.