Lindy,

On Tue, 3 Jan 2006 21:00:56 +0200, Lindy Mayfield wrote:

> I was installing ceiling lights in the new house and wanted to be "smart" and double check to see if the 
exposed wires were hot or not.  So I connected my multimeter first just in case.  I grew up in the US so I am 
not very familiar with connecting things here in Europe and I wanted to be careful.  
> 
> I was a little surprised when my meter showed first around 118 or so volts AC and then when the switch was 
flipped it jumped up to about 230.

Where were measuring, across the Live/Neutral, or Live/Earth?

> This kind of made me nervous, so of course I made the shorts test with what I thought was the off position 
before proceeding.  (The shorts test is when I touch the wires together and then check my shorts for signs of 
electrocution.)

LOL!
 
> Needless to say I survived, but I was wondering why I was getting a ~120 volt reading when the light switch 
was off?

First it could be wired as switched neutral - I've found a number of houses in England like this - very dodgy 
because across the wires reads dead, but one side is live.  This is something that catches you out once only!  
:-)

Secondly a multimeter has a very high impedance, so you may be measuring the voltage induced by the wiring.  
The only safe way to work on a circuit is with it isolated - at the distribution board, not just at the 
switch.

Cheers,


Howard Winter
St.Albans, England


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