Static shock from light switches even with power off??

[coxyboy]

I was called out to a job today and found something I have never come across before....
when I got to the property the tenant explained what was happening - she was getting what she called a "shock" when ever she turned the lights on upstairs in the two bedrooms and the landing. So I tested to see if there was any voltage at each switch and there wasn't. But sure thing as soon as I touched the switch I got a shock. I would say it was more of a big static shock than a normal voltage shock. So I had a little play around to investigate.

ie removing each switch reterminating and making sure the earths were connected. But still no joy. I turned off the main switch so there was no power to any circuit but I was still getting the static from each switch in both bedrooms and on the landing.

Has any one ever come across this problem before? If so what did you do to solve the problem??

Any help would be much appreciated, thanks

 

[Sintra]

Saw this in a house that had a cheap nylon type carpet and once this was changed no more static shocks.

 

[KAS1]

Nylon carpets lol

 

[dan86]

Saw this in a house that had a cheap nylon type carpet and once this was changed no more static shocks.

....+1

 

[Mork]

Do a Zs test at the affected switches, you may be floating.

 

[TaffyDuck]

Ditto.

Cheapo carpets. Disconnect the cpc and you`ll see it wont happen, assuming there is no path to earth elsewhere. Changing the switches to plastic ones or if they already are, putting plastic screw covers over the set pins will solve it. Cheaper than new carpets. May still happen on ovens etc though.

 

[plugsandsparks]

If you add underfloor heating to the mix, those pesky metal lights switches become lethal from static. Static likes dry atmosphere and its coming from the carpets. They might find its better in summer when the humidity rises.

 

[oldtimer]

Yep change switches to the ones that have plastic covers on the screw because the tenant is earthing themselves another thing is tell the customer to run the back of her hand on the wall or staircase either that ditch the cheap nylon carpet

 

[Happyneiller]

Agreed - static

 

[markc123]

Go round tomorrow and rip the carpet up whilst acting like an Ape.

 

[markc123]

If she says 'what the F' tell her its for the greater good

 

[lushers]

I had this very same thing today but the only difference was each it was various light fittings on the circuit; it would either be on the fixing screws or the terminals themselves, either through my hand or i would get a small spark through my voltage testers. The other difference was that unlike nylon carpets it was mostly laminate flooring. Help......

 

[Marvo]

I had this very same thing today but the only difference was each it was various light fittings on the circuit; it would either be on the fixing screws or the terminals themselves, either through my hand or i would get a small spark through my voltage testers. The other difference was that unlike nylon carpets it was mostly laminate flooring. Help......

Can you give a better explanation? What terminals and what voltage testers?

 

[lushers]

I was just using my combi check testers to check for voltage, it would happen at whichever terminal I put my first probe on. having looked at other threads similar to this I think it might be a build up of static from the laminate flooring.

 

[Marvo]

I'm not buying the 'static from laminate flooring' theory to be honest. I'd test to a wander lead connected to the MET. Maybe do a Ze test first as well.

 

[lushers]

Did a ze test and it was more than adequate, I've just finished rewiring the place, it was only when installing a fitting that we noticed/kept getting shocks. there are a couple of those 28w 2d fittings that I've installed, could it be anything todo with the control ballasts within these? will do a wandering lead test tomorrow, thanks for the advice

 

[ferg]

........

 

[telectrix]

get the carpet sprayed to eliminate the static.

 

[UNG]

Had a lad working for me many years ago that could walk up and down a few times then point his finger near the switch and get a spark to jump across to it told one customer the problem was down to the cheap (£4k) carpet he had bought didn't go down well

 

[Engineer54]

Static can build-up in your clothing, it's not all to do with carpets and other floor coverings. Static can be a real bugger to get rid of at times too!!