Abstract: A dehumidifier for an electrical-equipment air intake has an outer housing wall and a floor of a material with a high specific thermal conductivity downwardly closing the outer housing wall, having a downwardly tapering funnel-shaped inner surface formed with a central downwardly open port, and having a rounded edge where the surface meets the port. An inner air-permeable housing inside the outer housing wall holds a moisture-absorbing mass so that air drawn in through the port can pass through the mass and then into a space between the inner and outer housings. A moisture sensor is provided between the housings and a heater in the mass. A controller connected between the heater and the sensor energizes the heater and cooks moisture out of the mass such that the moisture condenses on the floor and runs over the edge out through the port.

Abstract: A pressure-relief valve has a flange formed with a throughgoing port. A spring plate spaced outward from the port is mounted on a rigid post fixing the spring plate relative to the flange. A valve body between the plate and the flange can shift between a closed position engaging the seal and closing the port and an open position spaced outward from the port and permitting flow through the port; A spring braced between the spring plate and the valve body urges the valve body into the closed position. A cup-shaped housing covering the valve body, spring plate, post, and springs has an end wall spaced from the flange and a side wall projecting from the end wall toward the casing and formed with a vent opening.

Abstract: The invention relates to a decompression valve for oil-cooled step switches and transformers. The inventive decompression valve comprises a valve lid which is actuated by springs and closes the non-operating valve, said springs being arranged between said valve lid and a spring lid. Said decompression valve is entirely placed in a body (18) which is embodied in the form of a pot and fixed directly to a flange (1) and provided with an output opening (26) in the pot-shaped lateral area.

Abstract: A dehumidifier for an electrical-equipment air intake has an outer housing wall and a floor of a material with a high specific thermal conductivity downwardly closing the outer housing wall, having a downwardly tapering funnel-shaped inner surface formed with a central downwardly open port, and having a rounded edge where the surface meets the port. An inner air-permeable housing inside the outer housing wall holds a moisture-absorbing mass in the inner housing so that air drawn in through the port can pass through the mass and then into a space between the inner and outer housings. A moisture sensor between the housings and a heater in the mass are connected to a controller that energizes the sensor and cooks moisture out of the mass such that the moisture condenses on the floor and runs over the edge out through the port.

Abstract: An air demoisturizer for an oil expansion vessel of an electrical power unit like an oil-filled transformer, tap changer or choke, has a heating element in the body of absorbent and utilizes a heat-regeneratable absorbent which is cut off by a moisture detector from the oil expansion vessel when the absorbent is saturated and is thermally regenerated. The demoisturizing column is provided in line with an oil receiver through which the dry air is passed before reaching the oil expansion vessel.

Abstract: An air demoisturizer for an oil expansion vessel of an electrical power unit like an oil-filled transformer, tap changer or choke, has a heating element in the body of absorbent and utilizes a heat-regeneratable absorbent which is cut off by a moisture detector from the oil expansion vessel when the absorbent is saturated and is thermally regenerated. The demoisturizing column is provided in line with an oil receiver through which the dry air is passed before reaching the oil expansion vessel.