Why do bushings exist?

Please don't post the Wikipedia explanation.

As far as I have learned, environmental contaminants can accumulate on the insulation surrounding the live conductors. This will distort the electric field potentially causing an insulation failure which causes current to travel along the outside of the bushing.

 If the bushing is cylindrical this current is virtually un-dampened by the time it reaches the housing of the breaker, transformer etc. Whereas if the bushing is corrugated the current must travel along a much longer resistive path which lowers the current magnitude.


Can anyone verify/correct/elaborate on this?

asked 1/8/2014
William York2
William York

1 Answer

Bushing is needed for incoming and outgoing currents to transformers and switch gears.Since bushings are installed, the connecting contacts to these devices remain protected from external shortings and weather conditions etc. As bushing material is a high insulator,fiels distortion will be less..
answered 12/6/2014 inspector salim 5
inspector salim

Your Answer

In order to provide an answer to this question, you must Login

I am flagging this question because...

10 inform moderator flags remaining

I am deleting this question because...

I am flagging this answer because...

10 inform moderator flags remaining

Flagging a Post

You have already flagged this post. Clicking "Remove Flag" below will remove your flag, thus reducing the count by one as well.

I am deleting this answer because...

Fire Resistant and Fire Retardant Cables

Fire resistant and fire retardant cable sheaths are design to resist combustion and limit the propagation of flames. Low smokes cables have a sheath designed...

Always Use PPE

A lot of our members work in countries where PPE (personal protective equipment) is regulated or they work for companies/organizations which take employee...

How to Write an Electrical Note

Electrical notes are a collaborative collection of electrical engineering information and educational material. Any registered user can add content. ...

Differential protection, the good old days

This morning I was explaining how differential protection works to a junior engineer. To give him something to read I opened up the NPAG (Network Protection...

9 power supply issues solved by using a UPS

Installation of a UPS can help in reducing problems due to issues with the power supply.  A lot of people relate this to nine key issues.  Depending on...

Skin Tapping Input

Tapping your forearm or hand with a finger could soon be the way you interact with gadgets. A new technology created by Microsoft and Carnegie Mellon ...

HTML Symbol Entities

HTML supports a variety of entity symbols which can be entered using either numbers or an entity name.  The number or name is preceded by the ‘&’ sign...

Harmonised Cable Codes and Colours

Within Europe the European Committee for Electrotechnical Standardization (CENELEC) has standardised the both the designation and colour of cables.   ...

Paths of Flight

GE have put together a time-lapse video shown flight take-off and landings at some airports. An interesting view:

RLC Circuit, Resistor Power Loss - some Modelica experiments

Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development...

Our website uses cookies so that we can provide a better experience.
To learn more about what cookies are and how to manage them visit AboutCookies.org