dust

I was just wondering if dust is generally a conductor or insulator.

Also, how can dust often cause electronics equipment to malfunction
without usually breaking it completely?

 

Generally an insulator, or very poor conductor.

Dust most often causes problems by enveloping hot components
in an insulating layer, that causes their temperature to
rise. It is the temperature that damages the components,
not current through the dust.

In high voltage equipment, it may help form carbon tracks
that leak current around insulation.

 

In addition, dust may attract moisture.

Graham

 

** It is generally an insulator.

But what it " generally" is is a total irrelevance when compared to the
monster it can sometimes be.

** By blanketing hot running parts and thereby preventing cool air flow
from doing it job - causing overtemp automatic shutdowns and intermittent
temporary malfunctions.

Moist or wet dust is a partial conductor, a corrosive agent to metal
surfaces and an initiator of high voltage insulation failure.

Very bad news.

Electronics needs to be kept clean.



........ Phil

 

The answers given by other respondents are all spot on...

If you want to see the effects of dust laden electrical components
first hand wait until the first shower of rain after a long dry spell
and stand near a high voltage ac power line. You may hear a continuous
sizzling, spluttering or crackling sound as the high voltage tracks
across the insulators using the moist dust layer as a conductor. At
night time you can sometimes see the blue arcs tracking across the
insulators. That same dust was there in its dry state before the rain
but because it is an insulator it causes no real problems. Add water
and the problems begin - pole-top fires and arc-overs etc.

Power distribution organisations will usually embark on a program of
high pressure cleaning of pole insulators before the onset of winter
to minimise the possibility of hazards from these situations.

 

And once it is wet it is a conductor, if not a good one.

Sandy