Electrical sensation on metal light switches?

[JackFrost]

We noticed recently that a couple of the wall switches to the lights give an electrical sensation when touched. Is this due to poor earthing, cables, or connections on the light circuit?

 

[andy]

We noticed recently that a couple of the wall switches to the lights give an electrical sensation when touched. Is this due to poor earthing, cables, or connections on the light circuit?

i assume you have metal switches then. these MUST be earthed. if they were properly earthed, you would not get a shock. look into it ASAP, you might have to call an electrician

 

[Lectrician]

If they where earthed, and you get a tingle, there must still be another problem.

Do not try it, but do you get 'sensations' off of any other metalwork in the house?

I suspect a live to earth fault somewhere, either through a resistance, or a direct short. This coupled with a TT supply and a dodgy RCD. The earth resistance of the rod in a TT supply is usually too high to allow the necessary fault current to flow to pop the appropriate fuse.

I have seen this countless times, and this is why I dislike TT supplies.

 

[JackFrost]

Yeah, I get the same sensation on some light fittings (also metal). Sometimes it is really obvious, sometimes it is verty slight. Note that some metal switch fronts don't give the sensation, about 50/50 in the house and, the upstairs and downstairs are on the same circuit. There is no RCD fitted only mcb and switch.

 

[towman]

Get it checked - but if no faults are found it could also be static electricity. Given the right conditions it's possible to build up quite a charge which can lead one to think there's a problem with the electrics when its actually that nice new wool carpet and rubber soled shoes!

 

[Lectrician]

Static electric would drain to earth if the earth conductor was intact.

I susspect you have 2 faults. A Live to earth fault on the lights, and lack of earth (either on just the lights or the whole house).

Get this checked out ASAP!!!

 

[plugwash]

quite right the static electricity on your body would drain to earth through the switch giving you a shock.

 

[felix]

I think the earth for most, if not all, of your lighting circuit is missing. When the earth wire is floating, capacitive coupling between cable cores brings it up to about 120 volts which is quite enough to cause tingling. Static causes a one off shock when you touch the metal and then it's gone - until next time.

Everybody who has replied so far says you should get it checked ASAP. They're right. Do it yesterday!