摘要:
A tap changing assembly for power transformers having vacuum interrupters each of which is associated with a radio interrogated surface wave sensor capable of detecting whether the respective vacuum interrupter opens circuit in a timely manner. The sensors are interrogated by an interrogating unit transmitting high-frequency signals to the sensors and associated with a monitoring circuit responsive to signals received by the interrogating unit for signalling the status of the vacuum interrupter.
摘要:
The invention relates to a method for dehumidifying air and to an air dehumidifier. To this end, a filter element is provided that is filled with granular material that can be regenerated by baking out. For effecting this baking out, a heating device is provided that is only actuated when both a humidity sensor indicates that a humidity limit value has been exceeded as well as a relative pressure sensor or a comparable technical means indicates that, at the moment, no flow toward the oil expansion tank is recorded.
摘要:
A tap selector for a power transformer switchable under load is monitored by detecting the effective values of current and voltage of the drive motor of the tap changer. The power is calculated and from that the instantaneous torque and the latter is compared with setpoint values either of the torque and position of the tap selector or in terms of characteristic segments of the torque versus time graph with normalized segments of a setpoint graph so that, with serious deviation an immediate shutdown of tap selector operations is ensured or information can be generated as to trends or the need for maintenance.
摘要:
A method of monitoring a tap changer in which measured values representing the status of the tap change operation are associated with positions of the tap changer and the position range or time range for the tap change is subdivided into partial intervals for which characteristic values of the measurement are calculated by a calculating rule, e.g. averaging. These characteristic values are compared with stored parameter data and operation categories are established which are then used exclusively for the further information processing.
摘要:
The invention relates to a drive unit for a step switch for actuating switch contacts. The problem addressed by the invention is that of providing a drive unit for a step switch which is arranged closer to the step switch, guarantees a fast and safe actuation of the step switch and also has a compact design. The problem is solved by a drive unit which consists of a lift magnet arranged directly on the switch contact, which opens or closes the switch contact by applying a voltage.
摘要:
A liquid level indicator for an oil-filled transformer, power choke or tap changer in which a sensor part has a float which rises and falls with the oil level and rotates a sensor shaft and the sensor shaft is coupled to an indicator shaft on which a pointer is provided to cooperate with a dial. The gauge also includes a contactless angle encoder operating with a magnetic hub and coupled to the indicator shaft for outputting a signal representing the oil level.
摘要:
The invention relates to a power transformer with electronic components. The aim of the invention is to arrange the energy supply of the electronic components of a power transformer closer to the components and thus eliminate the disadvantages of the prior art. According to the invention, a stray field collector is brought into a stray field of the power transformer, whereby a voltage is generated.
摘要:
The invention relates to a method for controlling a heatable dehumidifier. The heating of the dehumidifier is to be actuated only when several congruent time windows within which a temperature gradient is greater than or equal to 0 could be determined during a certain period of time, i.e. the heating is to be actuated only when no air flows into the interior of the expansion vessel of the transformer.
摘要:
An electric power apparatus has a oil-filled vessel in which a float is connected to a float shaft that rotates as the float rises and falls with the level of oil. A level indicator has a display shaft extending along and pivotal about an axis, and coupled to the float shaft. An indicia display adjacent the shaft is swept by a pointer fixed on the shaft and juxtaposed with the indicia display go that the level of the oil in the vessel is indicated by the pointer. A disk fixed to the shaft has an outer periphery with a region of a shape having a radius varying angularly from one end of the region to an opposite end of the region. A noncontact proximity sensor is radially spacedly juxtaposed with the region of the disk for producing an output corresponding to the radial distance between the region and the sensor.
摘要:
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.