Tingle from a lintel!

Hi,
Assuming I need to sort this ASAP but just curious as to why we have just noticed a tingle from the kitchen lintel (i can see a metal edge so assume there's one under there). The property had an electrical inspection about 8 months ago?

Cheers ....Chris

If this tingle is persistant then you need to have it checked.

The lintel might be live (230 volts ) due to a damaged cable. If it is live then there is a serious risk of severe, possible fatal shock if it is touched while also holding or touching something that is earthed.

To get a shock ( or tingle ) requires two points of contact if any current is going to flow through the body. With a mild tingle from the lintel the other point of contact can be the person being in close proximity to something that is not at the same potential as the lintel. The contact is capacitive and the maximum current is there for very small.

There are two options.

Either the lintel has a voltage on it and you via the other point of contact are grounded
or the lintel is at ground potential and something is taking your body above ground potential.

What, besides the lintel, are you touching or very close to when you get the tingle from the lintel.?

It's just about possible that you are touching a lintel, but very much more likely that you are touching plasterer's bead, which will be on the square edge of the plaster around the doorframe. Silvery when new but oxidises to dull grey, and rusts if persistently damp.

Who did the electrical survey? Have you got a copy?

Is it a rented house?

Thanks Gents. We are standing on slate tiles which have underfloor heating but that should be switched off. There is a light switch under the door frame and some halogen lights in the ceiling. I do have a copy of the survey. I wonder if its always been like that or just happened? We did have some trips a few months back which seemed to be from the sockets but suspected the kettle eventually and once replaced that stopped. Only odd thing was that when the trip was activated I'd have to knock off the master breaker first and then wait a bit to reset the individual breaker. I will definitely get someone out ASAP.
Many thanks Chris

Pants!


Andy

And then, when you've done with the utter foolishness of trusting your life to a toy like that, you can use it to entertain the kids by making it light up by rubbing it on the arm of your jumper.

Photos of the lintel and all nearby electrics would be useful here.

Any curtain rails etc fitted?

Light switch under lintel on right and fridge and consumer unit to the RHS. Also underfloor heating )off) and lv roof lights.

I have thought about the problem, and how I would with my tools locate what is causing it. It is not easy as you have no idea if lintel is neutral potential, earth potential or line potential all you know is it's not the same as your potential.

I would start with the survey already done. This should show earth type TN or TT which is a good start. I am assuming RCD protection all circuits which would limit line - earth current to 30 mA however with TT system unless double pole RCBO's are used one could still get a earth - neutral shock with RCBO protection.

We look at "wall or partition the internal construction of which includes metallic part, other than metallic fixings such as nails, screws" and forget the metal used by plasterers until we see cases like Emma Shaw when I read the report I do wonder if I was the foreman would I have also taken the readings given to me as correct? But it does show how a fault can go undetected had there not been a water leak it could still be there today.

So using a volt meter simple enough to measure against the earth pin of a handy socket whoever showing voltage i.e. a fault is great, but if it shows no voltage then what? Point is proving something is dangerous is easy, proving it is safe is hard.

We should test the earth on every socket and every light switch and every ceiling rose. When I did my C&G2391 inspection and testing we were given a board to test about 5 foot square which took around an hour. If I was to test a house to the same degree it would take at least a day yet when my son was doing it for a living he was lucky to have 2 hours. And an hour of that was taken up writing down sizes of cables and cable types which in the main was a guess anyway. We talk about drive past inspection and tests and maybe not quite that bad, but until amendment 3 which I admit I have not read only been to talks, any where hard to access was missed.

I am told with amendment 3 even if it means removing tiles loft spaces should be inspected. Yes and that is really going to happen, I think not. Going silly means we have not a clue really what an inspection should include.

The fault may not even be in the house. Road works have been know to damage cables and cause voltage on the earth. Sorry not much help, as others have said it's a long job testing to prove OK, quicker if you find a fault. The volt stick is useless it would not help at all.

Thanks Eric.
Earthing is - TT, actually I'll post a pic

Interesting, I wonder where the fault lies? anyway it has nothing to do with supply, it has to be inside the house, from the paperwork you show I would assume a single 30 mA RCD supplies whole house, so it is unlikely there is a bad enough fault to kill you at least although clearly wants correcting. Reading the report it seems he did a good job. I have considered if there are any tests you can do. But I can't think of any DIY fix. It will need an electrician. Sorry.

No that's fine Eric. I wouldn't dream of DIY for any serious electrical issues, I was more curious as to the cause. I'm just trying Sparks now but everyone seems quite busy.

We sometimes have queries like this which technically should not happen but we never appear to hear the final outcome and reason.

Please let us know.

EFLImpudence said:

We sometimes have queries like this which technically should not happen but we never appear to hear the final outcome and reason. Please let us know.

Click to expand...

Indeed so. However, I suspect that with many of these 'tingles' issues, there is never any explanation discovered.

Kind Regards, John