Switchgear includes various switching devices such as switches, circuit breakers, off-load isolators, contactors, switch fuse units, HRC fuses, ELCBs, miniature circuit breakers, GFCIs etc.
It also comprises the grouping of these switching devices with measuring, associated control, protecting and regulating apparatus. The switchgear devices and their assemblies are put to use in connection with the generation, transmission, delivery, and conversion of electrical energy.
Numerous switching and protective devices are developed. Therefore, switchgear can be said as a general term covering various equipment concerned with the protection, switching, and control of numerous electrical equipment.
Function of a Switchgear
Switchgear performs the functions of carry, make and break the normal load current such as a switch.
Furthermore, it performs clearing the fault current for which transformers, and numerous relays, contingent on the application, are employed.
There is also a provision for controlling, metering, and data, wherein countless devices are used for attaining switching function.
Components of Switchgear
Switchgear has protecting and switching devices like fuses, circuit breakers, isolators, switches, control panels, protective relays, current transformers, lightning arrestors, auto reclosures, potential transformers, and numerous associated equipment.
Some equipment is intended to operate under abnormal and normal conditions. Some is meant for switching the fault.
Throughout normal operation, switchgear allows to switch off or on generators, distributors, transmission lines, and other electrical equipment. Instead, when a failure takes place on any part of the power system, heavy current flows through the apparatus, threatening damage to the apparatus and service interruption to the customers.
Though, the switchgear senses the fault and detaches the morbid section from the system.
Features of Switchgear
Enormous Dependability
With the constant trend of interconnection and the snowballing capacity of making stations, the necessity for dependable switchgear is very important.
This is not astonishing since it is added to the power system to advance reliability. On occurring of a fault on any part of the power system, they should operate to separate the faulty section from the rest of the circuit.
Able to Find Faulty Sections
On the occurring of a fault to any section of the power system, the switchgear can find out the faulty section and the sections which are fine. It isolates the faulty section from the healthy ones and not affecting the healthy section. This ensures continuous supply.