Abstract: A device for monitoring a leakage current of a surge arrester has a measuring element for detecting a leakage current in a leakage current circuit. A filter assembly filters the leakage current in order to extract a third harmonic oscillation which is evaluated by an evaluation circuit with respect to the value thereof. The evaluation circuit delivers at least one warning signal to a display device. In a preferred embodiment, three display devices operating as a signaling light are provided. A power supply for the used circuits is obtainable by way of a transformer which extracts a necessary auxiliary zero-potential energy contained in the leakage current and with the aid of a main power supply unit connected to the transformer.

Abstract: A wind turbine equipped with a tower, a nacelle rotatably mounted on the tower, a rotor rotatable at the nacelle about a rotor axis of rotation and including one rotor hub and at least one rotor blade which is coupled by a blade bearing to the rotor hub while rotatable about a blade adjustment axis. The blade bearing includes an inner ring firmly affixed to the rotor hub and an outer ring that is fitted with a toothing and that is firmly connected to the rotor blade The, rotor blade is rotatable by a blade adjustment drive including a drive motor actuating a drive pinion meshing with the outer toothing of the outer ring.

Abstract: An overvoltage arrester for high or medium voltage is described which includes an arrester block arranged inside a sealed, gas-tight enclosure housing, a sensor, in 5 particular a temperature sensor in the form of a surface wave sensor, is arranged inside the enclosure housing. The surface wave sensor is arranged in a housing that is designed as an antenna.

Abstract: Disclosed and claimed is a process for selectively separating hydrogen halides from sulfur-dioxide-containing gases by using an adsorbent made from a porous ceramic support material which is impregnated with an alkaline earth metal salt solution and, after evaporation of the solvent, the alkaline earth metal salt is pyrolysed at 200.degree. to 800.degree. C. to give alkaline earth metal oxide .Xh.sub.2 O, where x is a number from 0 to 1.

Abstract: Waste gas, in particular from plants for the chemical vapor-phase deposition and for the separation and etching by plasma processes, is purified from toxic agents by a method in which partial processes of the purification, such as thermal decomposition and oxidation, sorption of solid and gaseous reaction products, hydrolysis and cooling, are combined to act in a single reaction chamber. The reaction products of the waste gas burnt in a flame are led, directly in the combustion chamber, through a space filled with a finely dispersed liquid. This liquid forms a liquid film on all parts and inside walls of the reaction chamber. In a combustion chamber with a burner, the mentioned liquid distribution is obtained by a spraying device.Effective purification from toxic agents, and little corrosion of the components of the reaction chamber are achieved, any growth of solid reaction products in the combustion chamber being avoided.