problem with a live light switch plate.

Hi all. I have a problem with a dimmer light switch plate. when its touched there ia "buzzing" sound and a faint tingle.
uk 240vac supply tn-c-s (pme) earth system
I have measured from the metal face plate to earth and i get a reading of 80-100vac. The earth wire from the cable is conected to the metal back box and the face plate, the switch feeds a transformer for low voltage lighting.
what could be causing it? a broken earth somewhere maybe?
thanks in advance Ben
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Might be.. I was hooking up a GFCI outlet outside and couldn't figure out how it was measuring only 24 volts instead of 115. I got a slight tingle and my finger started to feel numb so I immediately stepped back. I checked the old connection to the house about 20 ft away and one of the twist locks had fallen off over the years and the wires were barely touching. If they had been connected I wonder if I would of been electrocuted with the full 115 volts...
Be careful
I guess the moral of the story is don't stand tingle.

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If this is a touch dimmer, then this is to be expected. It detects touch by leaking a tiny current through your body capacitance to ground.
If it's not a touch dimmer, then you may have a broken ground. If part of your lighting wiring installation is very old, it may not have earth conductors. In this case you must only use plastic switch plates and double insulated light fittings until you get it rewired.
--
Andrew Gabriel

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snipped-for-privacy@cucumber.demon.co.uk (Andrew Gabriel) wrote:

It's not a issue of whether grounding is intact or not (except that improper or no grounding compromises safety). There is a fault somewhere and that's where the problem resides. Sincerely,
John Wood (Code 5550) e-mail: snipped-for-privacy@itd.nrl.navy.mil Naval Research Laboratory 4555 Overlook Avenue, SW Washington, DC 20375-5337
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