GB369306A - Arrangement for protecting electric systems against excess voltages - Google Patents

Abstract

369,306. Protective arrangements. ETABLISSEMENTS MERLIN ET G•RIN, Rue de Monestier de Clermont, Grenoble, France. Jan. 8, 1931, No. 687. Convention date, Jan. 18, 1930. [Class 38 (iv).] An inductance coil or coils, which may assist the protection, are associated with the electrodes of a condenser, between which electrodes an arc is formed in discharging an excess voltage, in such a way as to extend the arc rapidly along the surfaces of the electrodes. As shown, the electrodes are concentric cylinders b separated by insulating walls a provided with one or more openings c through which the arc is formed and the inductance coil d is wound exteriorly on the condenser to cause extinction of the arc by extending it in the manner indicated in Fig. 3. The electrodes may be of any suitable shape and are connected between the circuit protected and earth with or without a series resistance; they may have a longitudinal slit to prevent absorbing circuits, but the inner cylinder may be solid to increase the field in the useful space. The electrodes and insulating walls are supported on a grooved insulating support and covered by a grooved insulating hood in order to prevent sparking between the electrode extremities ; the support and hood may have insulating ridges in the spaces between the electrodes. One or more inductance coils may be arranged on a magnetic core with polepieces causing a magnetic field between the electrodes.