After some advice: Mild tingle from shower when in use

333rocky333 · 23 Oct 2014

JohnW2 said:
I may be out of my technological depth here! Anyone?

Kind Regards, John

Theres not much in them, and the special bit seems deeply embossed in the tip.
I have various failed all plastic ones and would be happy to post you one to disect john

TheGovernor · 23 Oct 2014

[quote="scousespark";p="3227612 said:
";p="3227612"]Given you have paid at least enough over the year (I would imagine) to cover your services, I would get Homecare back out to find the fault.
Otherwise, you are paying twice.

Your experiment does demonstrate the problem you have. You got a result twice then nothing. Hopefully, you will get a positive reading next time an electrician is on site. Good luck mate.

Thanks mate

I have called BG, they're coming on Saturday AM, Will update when they've been, although as you can see I'm keeping at it

I've had a mooch around in the loft and not found anything of interest. Except for the fact that if I lean on a particular roof strut and put my volt-pen to the pipework it lights up! That seems related to a lighting cable being run along that roof strut - I guess I am acting as conductor between the lights and the pipes... although that doesn't sound right because it indicates a difference in potential..?

http://youtu.be/ivZuXe3n4JQ

Jackrae said:
Govenor,

Humour us.

I think you're humouring me, and I'm grateful for it!

Jackrae said:
Are the trays metal, plastic or ceramic and are the outlets metal or plastic.

The trays are plastic, with the drain having a metal rim (as you might notice in the videos below!!

Jackrae said:
Your light-pen display in the DNO box was useful in that it illustrates that they tend to produce poor objective evidence when chasing problems.

Indeed, these volt pens aren't great in tight spaces where cables are close together, or "emitting" a lot of voltage...

And so, more information, if you look at the videos below I took my cheapo multimeter and took some voltage readings, I think I've explained them on the video, but basically I took readings as follows:

Between the drain plug and the shower hose

Between the drain plug and the shower main body

Between the shower main body and the nearest radiator.

I was seeing readings of about 1.8V - so there is something there... but well within allowed tolerances?

More videos from the Amityville house of horror!

http://youtu.be/0TlxwpToWXQ

http://youtu.be/F9eABK-GDwY

http://youtu.be/PFXqB6OCuG8

flyingsparks · 23 Oct 2014

Having watched your video, if wonder if there used to be a pumped shower there. It may have been supplied by the lighting circuit and when removed the cable was left in the wall.mnow when you wet the wall the plasterboard is getting damp and causing a high resistance path to the live cable in the wall. If you go in the loft can you see any cables dropping down the wall above the shower location?

JohnW2 · 23 Oct 2014

scousespark said:
Your experiment does demonstrate the problem you have. You got a result twice then nothing. Hopefully, you will get a positive reading next time an electrician is on site. Good luck mate.

Indeed - and if if it doesn't happen next time an electrician in on site, at least the OP can show him/her the videos.

Kind Regards, john

JohnW2 · 23 Oct 2014

333rocky333 said:
Theres not much in them, and the special bit seems deeply embossed in the tip.

That's interesting. Of course, whether one could identify the nature of 'the special bit', even if one got at it, is perhaps a different matter!

333rocky333 said:
I have various failed all plastic ones and would be happy to post you one to disect john

That's very kind, and I might even take you up on that. However, I know that a friend of mine had a dead one, so if he hasn't thrown it out, I could probably get it off him. I'll check.

Kind Regards, John

EFLImpudence · 23 Oct 2014

TheGovernor said:
if I lean on a particular roof strut and put my volt-pen to the pipework it lights up!

I don't exactly follow what you mean but could your leaning on a strut be putting pressure on a joist causing the pipe to come into contact with a (worn) cable which it may do when it expands when hot?

JohnW2 · 23 Oct 2014

Thinking aloud ... I'm starting to wonder whether all the OP's investigations and experiments are telling us about little other than the idiosyncracies, unpredicability/variability and 'unreliability' of these various 'voltage detecting' gizmos and that maybe the truth is that there is no real 'problem' - i.e. that any true potential differences between anything and anything else are extremely small.

As I understand it, the tingling the OP has experienced has been mainly/always experienced in broken skin. Once the highly protective (and quite insulating) skin is broken, the exposed tissues can be very sensitive to even very low voltages, particular if wet - as many/most people know if they have tried a battery on their tongue (although, admittedly, a lot of that is due to electrolysis)!

Kind Regards, John

EFLImpudence · 23 Oct 2014

http://www.testequipmentdepot.com/a...derstanding-capacitive-voltage-sensors_an.PDF

Jackrae · 23 Oct 2014

Not only microwave, such device types are often used professionally as "indicative" devices ("indicative" as never to be trusted) for use on mains frequency systems

JohnW2 · 23 Oct 2014

EFLImpudence said:
http://www.testequipmentdepot.com/application-notes/pdf/electrical-test/understanding-capacitive-voltage-sensors_an.PDF

Thanks, but that is talking about the standard capacitive coupling method which we all 'know and love', relying on capacitive coupling to earth through the body of a person holding the barrel of the device ...

Mr Fluke said:
The capacitive voltage sensor works because when you hold the barrel in your hand and place the tip near a live conductor, you are inserting the high impedance sensing element into a capacitively coupled series circuit. As in the previous example, your hand and body form a relatively large capacitor coupled to the floor. The sensor tip is a small capacitor coupled to the live voltage.

That does not therefore solve the mystery of those devices which (if they exist

) you say can sense voltage even when not being held - unless the device itself has enough capacity to earth (which I would doubt).

Kind Regards, John

EFLImpudence · 23 Oct 2014

I was holding it in a pair of 1000V insulated grips; can it go through them?

I note the article said if you rest the detector on a pile of books while 'touching' a live wire it does not light.

securespark · 24 Oct 2014

JohnW2 said:
An electrostatic field (which is what you say Fluke are talking about) is a different kettle of fish,

When I rub my volt stick up and down my arm, it lights up.

And no, that's not a euphemism.

deadshort · 24 Oct 2014

But not after a few pints.

ban-all-sheds · 24 Oct 2014

I've used one as an aid to cable identification.

TheGovernor · 24 Oct 2014

JohnW2 said:
Thinking aloud ... I'm starting to wonder whether all the OP's investigations and experiments are telling us about little other than the idiosyncracies, unpredicability/variability and 'unreliability' of these various 'voltage detecting' gizmos and that maybe the truth is that there is no real 'problem' - i.e. that any true potential differences between anything and anything else are extremely small.

As I understand it, the tingling the OP has experienced has been mainly/always experienced in broken skin. Once the highly protective (and quite insulating) skin is broken, the exposed tissues can be very sensitive to even very low voltages, particular if wet - as many/most people know if they have tried a battery on their tongue (although, admittedly, a lot of that is due to electrolysis)!

Kind Regards, John

Ignoring the fact that in that event I've wasted the time of you good people, I am very attracted to the idea that I am just being hyper-observant, and am in fact experiencing what many don't normally notice.

That said, I continue to investigate... I couldn't get any "reading" off my volt-pen this morning post shower, however I did take some readings with my meter.

Referring back to last night when I was showing you all reading of 1.9v between the waste and the shower assembly, I took readings today after a shower and the voltage was 5.9v.

After about 5 minutes the voltage dropped to 4.5v.

I then got my (now groaning) wife to switch off the upstairs light circuit at the CU and the voltage dropped to about 1.3v immediately.

Got her to put it back on, straight back to 4.5v.

So, regardless of the fact this is all in the acceptable range (i.e. up to 50v) the light circuit is doing something weird with respect to the shower... probably not a completely loose earth, but maybe a poor one?

If nothing else, I am learning something, just not sure what yet

Every day is a school day!

I'm even getting the kids involved lol

Post shower

http://youtu.be/OYMOtyfdFTE

Light circuit going on/off

http://youtu.be/Kc64ibmKKLI

Checking against sink taps

http://youtu.be/mpJ8Q7LilSo