Bushing (electrical)

Bushing (electrical)

A bushing is an electrical engineering component that insulates a high voltage conductor passing through a metal enclosure. Bushings appear on switchgear, transformers, circuit breakers and other high voltage equipment.

Description

The bushing is hollow, allowing a conductor to pass along its centre and connect at both ends to other equipment.Bushings are often made of wet-process fired porcelain, and may be coated with a semi-conducting glaze to assist in equalizing the electrical stress along the length of the bushing.

The inside of the bushing may contain paper insulation and the bushing is often filled with oil to provide additional insulation. Bushings for medium-voltage and low-voltage apparatus may be made of resins reinforced with paper. The use of polymer bushings for high voltage applications is becoming more common. The largest high-voltage bushings made are usually associated with high-voltage direct-current converters.

Capacitor types

Some of the higher voltage types (layers of paper, film and aluminum coil used as insulating medium) are called capacitor bushings because they form a low value capacitor between the conductor and the wall. This is done to reduce the electrical field stress that would otherwise occur and cause breakdown.

Bushing failure

Bushings sometimes fail due to partial discharge degradation in the insulation. There is at present great interest in the electricity supply industry in monitoring the condition of high voltage bushings.

ee also

In mechanical engineering, a bushing or Plain_bearing refers to a part which allows a rotating component to pass through a stationary one, the bushing carrying the load.

References

*cite book | author=Central Electricity Generating Board | title=Modern Power Station Practice |publisher=Pergamon | year=1982 | id=ISBN 0-08-016436-6


Wikimedia Foundation. 2010.

Игры ⚽ Поможем сделать НИР

Look at other dictionaries:

  • Bushing — A mechanical bushing is a cylindrical lining designed to reduce friction and wear inside a hole, or constrict and restrain motion of mechanical parts. Bushing types One type of bushing is the threaded insert , a hardened metal insert with a… …   Wikipedia

  • Electrical conduit — risers, seen inside fire resistance rated shaft, as seen entering bottom of a firestop. The firestop is made of firestop mortar on top, rockwool on the bottom. Raceways are used to protect cables from damage …   Wikipedia

  • Insulator (electrical) — Ceramic insulator at railways Conducting copper wire insulate …   Wikipedia

  • List of oil field acronyms — Contents 1 # 2 A 3 B 4 C …   Wikipedia

  • проходной изолятор — Изолятор, предназначенный для провода токоведущих элементов через стенку, имеющую другой электрический потенциал. [ГОСТ 27744 88] проходной изолятор [IEV number 151 15 40] EN (insulating) bushing insulator forming a passage for a conductor… …   Справочник технического переводчика

  • Transformer — This article is about the electrical device. For the toy line franchise, see Transformers. For other uses, see Transformer (disambiguation). Pole mounted distribution transformer with center tapped secondary winding. This type of transformer is… …   Wikipedia

  • Lathe (metal) — Center lathe with DRO and chuck guard. Size is 460 mm swing x 1000 mm between centers A metal lathe or metalworking lathe is a large class of lathes designed for precisely machining relatively hard materials. They were originally designed to… …   Wikipedia

  • industrial glass — Introduction       solid material that is normally lustrous and transparent in appearance and that shows great durability under exposure to the natural elements. These three properties lustre, transparency, and durability make glass a favoured… …   Universalium

  • Meldin — 7000 is the trademark of a high performance polyimide polymer manufactured by Saint Gobain Performance Plastics ( [http://www.rulon meldin.com] ).History of the Meldin product lineMeldin is a family of polyimide materials and has been present for …   Wikipedia

  • U.S. Military connector specifications — Connectors used by the U.S. Military are described in military specifications documents, with the format MIL C 26482 (older format) or MIL DTL 26482 (current format). These differ in purpose from military standards (e.g. MIL STD...) in that… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”