[sdiy] iec connector confusion

[harrybissell at wowway.com]

Watch out (your understanding is incorrect :^)

In the USA there is (in theory) no potential difference between
Neutral and Earth.  There is 120VAC from "Hot" to Neutral and Hot
to Earth, but no difference between Neutral and Earth. Earth exists
as a safety return should there be some problem internal to connected
equipment.

That said... its very possible to have wall outlets that are reverse wired.
Connecting "neutral" from one chassis to another (if they are not wired
the same) can cause hot-to-neutral shorts. This is a MAJOR problem with
line referenced Tube Guitar amps, but seldom an issue with synths.

If your circuit (internal to the synth) goes ~only~ to a transformer
primary... the phasing of the wires will not cause a safety issue.  Connect
the Earth terminal to your metal case and you should be safe.

220V carries the same risks at double the voltage.

(I use "balanced power" with a special tapped transformer that truly gives +/-
60 volts with respect to ground. GOD help you if you mix wires from the
standard 120V system and the balanced one... :^)

H^) harry


On Tue, 28 Oct 2008 16:21:58 +0000, Graham Atkins wrote
> I would be careful here. It is my understanding that in the US, your 
>  Live & Neutral are split 50/50 with respect of earth. so your 
> potential  ideally on either leg would be no more than 55V in 
> theory. As the IEC is used in many  countries now it can be much 
> different. In the UK we have 240V but the Neutral  is (In perfect 
> conditions) at the same potential as earth with the Live at  240V so 
> it is seriously important that the Live, Neutral & Earth are 
> connected to  the defined L,N & E terminals.
> 
> Graham
> 
> On 28 Oct 2008, at 15:22, Jason Tribbeck wrote:
> 
> > Hi,
> >
> >> The :"neutral" (a white wire or silver/tin terminal) connection is  
> >> the
> >> grounded line, "ground" is the mains/earth ground line, hot should go
> > to the
> >> other (usually a black wire or copper/bronze terminal). Never connect
> > the
> >> hot wire to the case!
> >
> > It was my understanding that the three connectors should be labelled
> > with "L", "N" and an earth symbol.
> >
> > They are also in this shape:
> >
> >
> >    []
> >
> > []    []
> >
> >
> > The one in the middle (top) is earth. The other two are live and  
> > neutral
> > (doesn't matter which way around it should be).
> >
> > If N was connected to the case, then I believe that would be a  
> > **very**
> > bad thing to do.
> >
> > Oh - I'm assuming it's an IEC320 C13/C14 style connector.
> > (Unfortunately, the Wikipedia article -
> > http://en.wikipedia.org/wiki/IEC_connector - does not mention which is
> > which).
> >
> > A quick bit of searching has produced this:
> >
> > http://www.powerfig.com/iec60320-15-amp-power-cords.aspx
> >
> > Which means:
> >
> >        [] EARTH
> >
> > LIVE []    [] NEUTRAL
> >
> > (assuming it's the socket on the back of the unit, rather than the  
> > plug
> > itself).
> >
> > -- 
> > Jason Tribbeck
> >
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> >
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Harry Bissell & Nora Abdullah 4eva