On Fri, 16 May 2008 09:36:48 +0300, "Iain Churches"
<IainNG@[EMAIL PROTECTED]
> wrote:
>I have seen posts in which people from the US
>refer to "cheater plugs" I have a feeling they may
>have somnething to do with solving hum and ground
>problems.
>
>Can someone please enlighten me?
A cheater plug has the safety earth pin missing. Or, rather, that's
how it's used.
It has a 3 pin AC receptacle on one end with a 2 prong plug *and* an
earth terminal (sometimes a wire) that is *supposed* to be secured to
the wall plate center mounting screw (or 'something') to make earth
through the conduit. Or so the theory supposedly goes, except there's
not a single blooming residence in the U.S. that had *conduited* two
prong outlets so there's no earth to connect the thing to even if one
were inclined to futz with it. The 'normal' technique is to simply
plug your 3 prong cord into it and it into the 2 prong outlet.
The 'purpose' was "how do I plug my nice safely earthed 3 pin
appliance into my unsafe 2 prong outlet?" with the other common
approach being Mr, G. Q. Public gets a pair of tin snips and bye bye
earth pin.
A final note, the 'ground' pin on the cheater plug is larger than the
other so it can (supposedly) only be inserted the 'proper' way.
Unfortunately, in the U.S. it seems that two prong wiring is semi
random and 'ground' might be on either pin, depending on how
incompetent the builder's 'electricians' were.
As for the other purpose, 'hum', the intent is to break the earth.
On 'professional' wiring, the first 'commercial' job I did (eons ago)
was designing and building a small theatrical lighting console for a
High School. The school did the 'right thing' and had a professional,
licensed, electrician install the necessary 240VAC circuit.
Se we arrived on site, plugged our unit in, and the magic moment came.
With everyone watching and eagerly anticipating their first experience
with 'theatrical lighting' on their new stage we flipped on power and
instantly a clap of thunder blasted through the corridors as the main
breaker down the hall rocketed off plunging the entire wing into
darkness. Sort of the reverse of what we expected from a 'lighting'
console.
My 'first job' and I might have contemplated suicide if I hadn't been
stunned to brain dead. But as consciousness crept back... it *can't*
be the console.
I kid you not, only 3 freaking wires on an AC outlet and NOT ONE of
them was on the right pin. But, of course, WE could not fix it because
WE were not 'licensed electricians'. Had to get the 'expert' back out
for that.
>Iain
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