Hi Scott I seem to remembr on what we call double insulated 2-wire units
that you should not be able to touch metal with a British Standard childs
finger :-)) i.e via vents etc.
Alan
----- Original Message -----
From: "Scott Tilley" <[email protected]>
To: <[email protected]>
Sent: Monday, October 10, 2011 10:38 PM
Subject: Re: LF: mains wires
On 10/10/2011 1:19 AM, mal hamilton wrote:
> Tnx Scott and others for the info. Your system is more complicated
> because of the 117 v and 230v dual supply required.
> In the UK there is more conformity to wiring and the plugs are non
> reversible into the socket, whereas your 2 blade plug goes in either
> way round and no Earth. In EU their 2 pin plug is also reversible but
> does have an earth.
There is a conformity here too. Just different!
Ours is non-reversible as well. The neutral blade on a reinforced
insulation class plug set is wider than the hot so you can't switch them
around.
There are two main ways to achieve safety from electric shock in
equipment design:
1) Supply the equipment with a ground conductor and bond it to all
conducting surfaces. I.e. a three wire cordset...
2) Reinforce the insulation such that it is unlikely to degrade and
ensure that is used throughout the appliance. Most often this is used
with non-conducting enclosures etc. This allows the use of a 2 wire
cordset. SPT-2 cord is the smallest allowed for most appliances. SPT-1
is only now allowed on lighting products there the wire is pulled into a
chain or otherwise protected...
> When using NA 117v equipment in the UK it is probably best to use a
> step down ISOLATION transformer, and rewire the 230v equipment
> mains cord to be compatible with all the other shack eqjuipment.
>
Yes it can be a trial to get equipment from around the world to
co-operate. It's even worse in industry where all of the complexities
and differences of the grids cause alot of headaches...
73 Scott
