shock from fixing screws

[muzz3]

Hi can anyone help
Iam getting a 80 volts shock from my 2 gang light switch fixing screws.
When the light is on the voltage increases to 130 volts.
one switch operates the ceiling light which is a metal fixture and that is live, the other switch operates 4 wall lights (metal)which again are live. When I disconnect the live wire at the switch I am still getting voltage of 80 volts and 20 volts at the earth wires for wall/ ceiling lights.
I also have the same problem with the other light switch but this only operates a ceiling light.
please can anyone help

 

[Taylortwocities]

Is there an earth conductor at the switch and at the light fitting
Is it connected to earth
Is it connected to the earthing terminal on the metal fittings?

If the answer to any of the above is no then you need to get it sorted, either by yourself or a competent electrician.

 

[muzz3]

Hi Taylortwocities
Thanks for your quick reply
All the switches and light fixtures are earthed.
But does that solve my problem as the earths are live.ie a live or neutral is touching a earth wire.
thanks

 

[GaryMo]

You may find that what you think is an 'earth wire' (CPC) has become disconnected at some point and is now subject to capacitive coupling.

 

[muzz3]

Hi
What does that mean
subject to capacitive coupling?????????

 

[333rocky333]

What two points are you measuring between, to get these voltages.

 

[muzz3]

Hi 333rocky333
measuring from the earth wire/back box or off the lamp fixture then to earth by a volt meter
cheers

 

[ColJack]

capacitive coupling...

The means of a charge being transfered from one wire to another where the 2 wires are run in close proximity and one of the wires has no path for the charge to disipate..

I'm not entirely sure this is the case with what you describe..

the earth may not be connected, but it sounds like a screw has nicked a switch wire when the covers are put on..

 

[GaryMo]

I suggested this because I came across a fault in exactly the same circumstances.
The cpc was connected at the switch but didn't arrive at the fitting. The switch feed/return had been jointed onto older twin cable with no cpc.

He needs an electrician with test equipment to investigate where the poor connection or lack of cpc is on that circuit as it's obviously not at the same potential as earth.
An insulation resistance test wouldnt go amiss either.