Abstract: A circuit breaker comprises a vacuum chamber in which a fixed contact and a movable contact are located. A compensating reservoir comprising a counter-pressure element is provided for a good contacting.

Abstract: A method for determining a quantity of a gas contained in a tank of an insulated switchgear. The method includes: (i) acquiring a first temperature and a second temperature measured by a gas temperature sensor respectively at a first instant and at a second instant during a calibration phase; (ii) acquiring a first pressure and a second pressure measured by a gas pressure sensor at the first instant and at the second instant; (iii) determining a steady-state model of the tank thermal exchanges from the first and second acquired temperature and from the first and second acquired pressure; (iv) acquiring a gas temperature, a gas pressure and an ambient temperature during a measurement phase and (v) calculating the quantity of the gas contained in the tank from the acquired gas temperature, the acquired gas pressure, the acquired ambient temperature and from the determined steady state model.

Abstract: The invention relates to an electric coil for current limitation in medium voltage networks and high voltage networks, for example an inductance coil, having a conductive coil wire which is wound to form a cylindrical coil, with the conductive coil wire being wound around a segment of a core which conducts a closed magnetic flux. The core is interrupted by at least one non-magnetizable gap with small thickness to reduce a saturation of the core even with high currents flowing through the electric gap.