The main job of medium voltage switchgear is save power distribution and work as a cost efficient electrical component. One of the basic utilities and functionalities of switchgear is to provide safety and security, that is disruption of short circuit and surplus, load the fault currents at the same time maintaining the service to the unaffected circuits. Switchgear also offers isolation of circuits from power supplies. Medium Voltage Switchgear is also used for enhancing system availability by letting more than one resource to provide for load.
Design, ratings, details and specifications of switchgear are laid down by large number of standards. In some of the countries, ANSI and IEEE standards are made use of, while some or rest of the countries use IEC standards, at times with the local national variations or derivatives. A single line up may perhaps integrate several different kinds of devices, for instance, vacuum circuit breakers, air insulated bus, and physically operated switches may possibly all subsist in the same row of cubicles.
Varied classification of switchgear could be made up by the present rating, by disrupting the rating. Besides, the switch gear could also be classified based upon the insulating medium, voltage class, By construction type, such as, Industrial, Marine, Indoor, outdoor, utility, marine and many more.
For getting sure about the safe operation sequences of switchgear, the trapped key interlocking offers predefined scenarios of operation. Indoor switchgear, for internal arc containment, could also be type tested. This particular test is significant for user safety like modern switchgear is competent of switching large currents. Switchgear is generally inspected by making use of the thermal imaging for evaluating the state of the system and calculating failures prior their occurring. The increasing knowledge of dangers linked with high fault levels has resulted in network operators stating the closed door operation for operating racking breakers and earth switches.