A method and a facility for filling a high- or medium-voltage gas-insulated electrical apparatus in which the insulating gas comprises a mixture of heptafluoroisobutyronitrile ((CF.sub.3).sub.2CFCN) and carbon dioxide. The method and the facility using a mixture of (CF.sub.3).sub.2CFCN and CO.sub.2 in pressurised liquid form which is heated to a temperature no lower than the critical temperature of the mixture.

A circuit breaker system has an SF6 tank having a wall, and an SF6 heating system. The SF6 heating system includes a heater disposed externally of the tank, and a radiator disposed on the wall inside the SF6 tank. The radiator is thermally coupled to the heater via the wall. The heating system is constructed to conduct heat from the heater through the wall to the radiator. The radiator is constructed to radiate the heat to the SF6 in the tank. A circuit breaker system has an SF6 tank having a wall, and a particle trap. The particle trap has a spar extending radially inward from the wall and a wing extending outward from each side of the spar. Each wing is spaced apart from the wall and forms a region having no electric field at the bottom of the tank adjacent the spar.

An apparatus for heating an insulation fluid in a medium-voltage or high-voltage switchgear comprises an infrared source which is adapted to emit infrared radiation of at least one wavelength. Thus, at least one vibrational or rotational mode of at least one component of the insulation fluid is excited by absorption of at least a part of the infrared radiation, and condensation of the insulation fluid is efficiently prevented by this direct heating of the insulation fluid. A closed loop temperature regulator is used to heat only when required. A circulator in a heating chamber further provides for a mixing of the insulation fluid, thus preventing steep temperature gradients.

A sulfur hexafluoride (SF6) insulated circuit breaker system has a tank constructed to hold a quantity of SF6; a circuit breaker having contacts insulated by the SF6; a heater operative to supply heat to the SF6; and a thermal capacitor in conductive engagement with the tank, and operative to store heat energy and constructed to conduct the heat energy to the SF6 in the tank. A thermal energy storage system for a sulfur hexafluoride (SF6) insulated circuit breaker system having a tank storing a quantity of SF6 includes a thermal capacitor operative to store heat energy and constructed to engage the tank and conduct the heat energy to the SF6 in the tank.

The invention relates to a method for drying a chamber comprising a predominantly protective-gas atmosphere in the chamber under positive pressure, which has an operating pressure p1 and a predetermined minimum pressure p.sub.min, wherein the minimum pressure p.sub.min of the gas chamber is monitored and the operating pressure p1 is greater than the minimum pressure p.sub.min, wherein the method comprises the following steps: a) removing of a partial quantity Vi of the protective gas from the chamber, wherein the partial quantity Vi is equivalent to the pressure differential p, which is smaller or equal to the differential between p1 and p.sub.min, b) introducing a partial quantity V2 of a dry or dried protective gas into the gas chamber up to a gas pressure p2, which is greater than p.sub.min and c) repeating method steps a) and b) after a predetermined waiting time t. The invention further relates to an arrangement for carrying out the method.

A circuit breaker system has an SF6 tank having a wall, and an SF6 heating system. The SF6 heating system includes a heater disposed externally of the tank, and a radiator disposed on the wall inside the SF6 tank. The radiator is thermally coupled to the heater via the wall. The heating system is constructed to conduct heat from the heater through the wall to the radiator. The radiator is constructed to radiate the heat to the SF6 in the tank. A circuit breaker system has an SF6 tank having a wall, and a particle trap. The particle trap has a spar extending radially inward from the wall and a wing extending outward from each side of the spar. Each wing is spaced apart from the wall and forms a region having no electric field at the bottom of the tank adjacent the spar.

A sulfur hexafluoride (SF6) insulated circuit breaker system having a controller coupled to at least two different sensor devices and operative to control a heat output of an SF6 heater based on signals from the sensor devices. An SF6 insulated circuit breaker system includes a controller coupled to a circuit breaker position indicator and operative to control an SF6 heater based on a signal from the contact position indicator sensor. An SF6 insulated circuit breaker system has a controller coupled to an SF6 density monitor and operative to control an SF6 heater based on a signal from the SF6 density monitor.

A sulfur hexafluoride (SF6) insulated circuit breaker system has a tank constructed to hold a quantity of SF6; a circuit breaker having contacts insulated by the SF6; a heater operative to supply heat to the SF6; and a thermal capacitor in conductive engagement with the tank, and operative to store heat energy and constructed to conduct the heat energy to the SF6 in the tank. A thermal energy storage system for a sulfur hexafluoride (SF6) insulated circuit breaker system having a tank storing a quantity of SF6 includes a thermal capacitor operative to store heat energy and constructed to engage the tank and conduct the heat energy to the SF6 in the tank.

A breaking chamber (1) for a medium- or high-voltage circuit breaker extending along a longitudinal axis (XX) and comprising: a pair of arcing contact (4, 5), at least one (5) of which is movable along the longitudinal axis (XX); an arc-blast nozzle (6); a blast chamber (7), having a volume V2 that is constant and that opens out inside the blast nozzle; a compression chamber (8), arranged substantially behind the blast chamber, and structures (73, 81) for putting the internal volume of the compression chamber (8) into communication with the internal volume of the blast chamber (7); and structures (14, 15, 50), disposed substantially behind the compression chamber (8), in order to deliver liquid, either into the compression chamber (8), or directly into the blast chamber (7).

A casing for a circuit breaker includes a main body, an annular tube, and a rupture device. The main body includes an end cover attached to an end of the main body. The annular tube extending from the end cover on an outside of the end cover. The annular tube includes a desiccant holder configured to house a desiccant configured to remove moisture from a gas inside the casing. The rupture device is configured to regulate pressure of the gas housed inside the casing and is detachably mounted to the annular tube at an end thereof remote from the end cover and/or the annular tube is detachably attached to the end cover, and wherein a spacing defined by the desiccant holder is accessible from an end of the annular tube.