Computer fan revving fast

espresso

Cat695 wrote: »

But the hoover is earthed.....the connector to the hoover is plastic.......with a length of plastic.....maybe connected to a plastic pipe (or metal) with even more plastic on the end......i think you'll find that much distance will stop any static

Are you sure about that? Lots of household appliances are in fact double insulated, our Electrolux vacuum does not have an earth wire!

The basic requirement is that no single failure can result in dangerous voltage becoming exposed so that it might cause an electric shock and that this is achieved without relying on an earthed metal casing. This is usually achieved at least in part by having two layers of insulating material surrounding live parts or by using reinforced insulation.
In Europe, a double insulated appliance must be labelled "Class II", "double insulated" or bear the double insulation symbol (a square inside another square).

Static charge can reduce the life of sensitive electronic components not simply killl them dead, so you don't necessarily know if you have actually done any damage.

:rolleyes:

Bob63

I'm surprised nobody has mentioned computer-specific vacuum cleaners. These small hand-held devices, often fitted with antistatic straps, are used by professional engineers to clean computer systems as part of routine preventative maintenance. Start blowing dust around a large computer centre with an air duster aerosol and you'll quickly find yourself kicked out!

superscaper

cheesy.mike wrote: »

I'm surprised nobody has mentioned computer-specific vacuum cleaners. These small hand-held devices, often fitted with antistatic straps, are used by professional engineers to clean computer systems as part of routine preventative maintenance. Start blowing dust around a large computer centre with an air duster aerosol and you'll quickly find yourself kicked out!

Probably because it's overkill. I've worked in electronic engineering labs and even clean rooms, I've never once used one or seen one ever be used either by technicians or engineers.