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these horns are spread farther and farther apart. Consequently, the arc is lengthened, cooled and
interrupted. Air-break switches are generally used outdoor for circuits of medium capacity such as
lines supplying an industrial load from a main transmission line or feeder. Air - break Switch Isolator Switch (ii) Isolator or disconnecting switch. It is essentially a knife switch and is designed to open a
circuit under no load. Its main purpose is to isolate one portion of the circuit from the other and is not
intended to be opened while current is flowing in the line. Such switches are generally used on both
sides of circuit breakers in order that repairs and replacement of circuit breakers can be made without
any danger. They should never be opened until the circuit breaker in the same circuit has been opened
and should always be closed before the circuit breaker is closed.
(iii) Oil switches. As the name implies, the contacts of such switches are opened under oil,
usually transformer oil. The effect of...
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This note was uploaded on 11/12/2012 for the course MBA 101 taught by Professor Muhannad during the Spring '12 term at Bradford School of Business.
- Spring '12