A rupture reduction system for fluid-immersed electrical equipment includes a turret for mounting of a bushing. The turret is expandable in volume in response to a surge in pressure of the fluid in the turret. The expansion volume can be provided by an expandable section of the turret, which may include a bellows.

A safety device is disclosed for a power transformer containing a cooling liquid, and can include a shaped body having an inner chamber which is suitable to be at least partially immersed in cooling liquid and inside which gas can accumulate; a first floating element and a second floating element suitable to be at least partially immersed in and moved by cooling liquid; and a switch suitable to be actuated by the first floating element when the gas accumulated is such that the level of the cooling liquid in the inner chamber reaches a predetermined first threshold level and by the second floating element when the gas accumulated is such that the level of the cooling liquid in the inner chamber reaches a lower predetermined second threshold level, respectively. The first and second floating elements can be mounted on and move linearly relative to one or more corresponding guiding supports.

A system for short-circuiting or grounding low-voltage and/or medium-voltage installations. The system includes at least one fault detection unit for detecting an arc and at least one signal-processing unit for processing signals from the at least one fault detection unit. The signal-processing unit is or can be connected to the fault detection unit for signal transmission. The system further includes at least one control unit which is or can be connected to the signal-processing unit for signal transmission, an electrical energy storage device in or on the control unit, and at least one fast-switching switching element having a mechanical energy store.

A system for short-circuiting or grounding low-voltage and/or medium-voltage installations. The system includes at least one fault detection unit for detecting an arc and at least one signal-processing unit for processing signals from the at least one fault detection unit. The signal-processing unit is or can be connected to the fault detection unit for signal transmission. The system further includes at least one control unit which is or can be connected to the signal-processing unit for signal transmission, an electrical energy storage device in or on the control unit, and at least one fast-switching switching element having a mechanical energy store.

A rupture reduction system for fluid-immersed electrical equipment includes a turret for mounting of a bushing. The turret is expandable in volume in response to a surge in pressure of the fluid in the turret. The expansion volume can be provided by an expandable section of the turret, which may include a bellows.

A subsea power distribution device and system. The subsea power distribution device includes a first watertight housing accommodating at least one transformer having a primary winding and at least one secondary winding, input terminals electrically connected to the primary winding and arranged to be connected to a remote power supply, an output terminal electrically connected to the at least one secondary winding, and switches located within the first watertight housing and arranged to open and close the connections between each secondary winding and a corresponding output terminal. Each output terminal is further connected to an overcurrent breaking device which is further arranged to be connected to a subsea power consuming device. The overcurrent breaking device is arranged in a second watertight housing separate from the first watertight housing and is filled with insulating liquid.

A tap changer assembly includes a tap changer assembly housing completely enclosing a tap changer volume and an overflow volume. The tap changer assembly includes at least a part of a tap changer located in the tap changer volume. The tap changer volume and the overflow volume are connectable to each other via an overflow assembly. When a pressure in the tap changer volume is equal to or higher than the predetermined overflow pressure threshold, fluid communication between the tap changer volume and the overflow volume via the overflow assembly is enabled, and is prevented when the pressure is lower that the threshold. when fluid communication is enabled, an area at least 10% of a largest internal cross-sectional area between the tap changer volume and the overflow volume is enabled for fluid communication via said overflow assembly.

The invention relates to a bursting device (1) for a high-voltage device (2). The bursting device (1) is suitable in particular for on-load tap changers or high-voltage transformers filled with a filling medium such as gas or oil. The bursting device (1) according to the invention has a bursting cork (3) with support blocks (7) arranged on the inner surface (3B). A shear pin (8) is in arranged in each receiving block (7), said shear pin being divided into a first portion (8A) and a second portion (8B). The first portion (8A) of the shear pin (8) protrudes into the receiving block (7). The second portion (8B) of the shear pin (8) is arranged below the circumferential edge (9) of an opening (5) of the high-voltage device (2).

A subsea substation system including: an oil-filled water impermeable enclosure; an AC-transformer, and at least one overcurrent device electrically connected to the AC-transformer, the at least one overcurrent device, the AC-transformer, and the electrical connections between them are accommodated in the oil-filled water impermeable enclosure, wherein the enclosure includes thermal zones within the enclosure, wherein the AC-transformer is arranged in a first thermal zone and the overcurrent devices are arranged in a second thermal zone of the enclosure, a thermal layer separate the first thermal zone and the second thermal zone, the at least one thermal layer is configured to allow oil flow between the thermal zones while reducing heat flow between the zones.

A subsea power distribution device and system. The subsea power distribution device includes a first watertight housing accommodating at least one transformer, having a primary winding and at least one secondary winding, input terminals electrically connected to the primary winding and arranged to be connected to a remote power supply, an output terminals electrically connected to the at least one secondary winding, and switches located within the first watertight housing and arranged to open and close the connections between each secondary winding and a corresponding output terminal. Each output terminal is further connected to an overcurrent breaking device which is further arranged to be connected to a subsea power consuming device. The overcurrent breaking device is arranged in a second watertight housing separate from the first watertight housing and is filled with insulating liquid.