Everything You Wanted To Know About Switchgear

By Author: Michael Jacob
Total Articles: 3
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Why is switchgear so important in an electrical system? Switchgear is the electrical equipment that regulates the flow of electricity within an electrical system. It is used in preventing short circuits, overloads and also to de-energize circuits for testing as well as maintenance. Circuit breakers and fuses are the most familiar types of switchgear. These switchgears interrupt the flow of electricity to a circuit when its current becomes too high and power transfer switches, which transfer a buildings source of electricity from a primary source to a secondary source, such as accessing generator power during a power outage.

Switchgear can be categorized as per its interruption technology and can be categorized broadly into oil circuit breaks, gas (SF6) breaks, vacuum breaks, air breaks and hybrid breaks. In the oil circuit breaks gear, oil is vaporized to send a jet of oil through an arc. The gas (SF6) breaks stretch an arc and then rely on the SF6 to extinguish it. The vacuum breaks extinguish their comparatively small arc by stretching it. The air breaks typically use a puff of air to extinguish an arc and the hybrid ...
... breaks use more than one type of breaking technology to extinguish an arc, such as gas and air.

There are several kinds of switchgear which serves various kinds of requirements. For instance, 11kv switchgear is suitable for indoor and kiosk installation. Whatever type the switchgear may be, its maintenance is extremely important to ensure worker safety as preservation of assets. This is because fatal fires are often caused by faulty electrical equipment.

Another term which has earned a name for itself is RETROFIT. It means the implementation of modern components (primary switching devices and digital protection/control technology) in the existing MV installation. Lmt Retrofit has the benefits of cheaper than a complete replacement, minimum shutdown of the switchboard, minimisation of further maintenance costs, spare parts availability for long time, improved operator protection, short implementation time for replacement, remaining service life extension and warranty on the conversion work.

High voltage switchyards and substations are an important component in the electrical generation, transmission and distribution system. It is true that low voltage designs are much in demand but high voltage design is required for many applications. In several situations, higher voltages are used for lower currents while minimizing IR loss and I2R heating.

Conductor spacing and associated dimensions are the beginning of high voltage dealing. Creepage and clearance are critical terms used for spacing conductors at higher voltages. What is creepage? Creepage is the ‘distance an arc may travel measured over a surface, such as between two traces on a printed-wiring board or across the surface of a connector or IC.’ Clearance is the ‘shortest distance an arc may travel through air, such as from the pin-to-pin of a connector or IC.’ High voltage designs require more than just routing current at high potential. The design also involves controlling and switching current at high voltages.

Like any other devices, electrical goods should also be brought of good quality and maintained properly to ensure its desired activity and longevity.

About the Author :-

Author Info: (Michael Jacob) is an electrical engineering professional. An expert with more than 20 years in this field, she is a regular columnist too. She writes for various renowned companies including RPS Switchgear, on topics such as High Voltage Desig and high voltage design.