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Controls for the reclosers range from the original electromechanical systems to digital electronics with metering and SCADA functions. The ratings of reclosers run from 2.4–38 kV for load currents from 10–1200 A and fault currents from 1–16 kA. [7] [8] On a 3-phase circuit, a recloser is more beneficial than three separate fuse cutouts.
We want to be a little careful - reclosers are only used on distribution circuits, not on the "grid" (high voltage transmission). True, some circuit breakers on transmission may automatically reclose but that's a special-purpose application and HV transmission circuit breakers aren't called "reclosers".
For example, since there is only one line, winds can't cause lines to clash, removing a source of damage, as well as a source of rural bush fires. Since the bulk of the transmission line has low resistance attachments to earth, excessive ground currents from shorts and geomagnetic storms are more rare than in conventional metallic-return systems.
The metering pulses were generated in a junctor circuit, at a rate set by the sender, usually one pulse every few minutes. Every month a worker read and recorded the indicated number of message units, similar to the accounting of a gas meter. In the middle of the 20th century it became customary to photograph the meters, about a hundred per ...
Examples are a voltage regulator (which can be a transformer whose voltage ratio of transformation can be adjusted, or an electronic circuit that produces a defined voltage), a pressure regulator, such as a diving regulator, which maintains its output at a fixed pressure lower than its input, and a fuel regulator (which controls the supply of ...
An automatic number announcement circuit (ANAC) is a component of a central office of a telephone company that provides a service to installation and service technicians to determine the telephone number of a telephone line. The facility has a telephone number that may be called to listen to an automatic announcement that includes the caller's ...
In 1956, Hugh C. Ross at Jennings Radio Manufacturing Corporation revolutionized the high-frequency-circuit vacuum switch and produced a vacuum switch with a rating of 15 kV at 200 A. Five years later, Thomas H. Lee at General Electric produced the first vacuum circuit breakers [2] [3] with a rated voltage of 15 kV at short-circuit breaking ...
The automatic lubrication system is connected to a control system via switchs. The control system may involve human input or may be computerised (computer numerical control or CNC). [2] [3] There are advantages of using an automatic lubrication system over a manual system. For example, there are savings in the costs of human resources. The ...