After some advice: Mild tingle from shower when in use

[JohnW2]

The volt stick you were using does not rely on anyone holding it. It will work while being held in insulated grips. Also the tip does not contact anything electrically and will work at a short distance away.

How do these things actually work?

I have no idea how they work

If they can detect the presence of voltage (relative to earth), I can see no alternative to them relying on capacitive couple to earth to give them the earth reference. The body of the device might (sometimes) itself have enough capacitive coupling to earth, but I would have thought that a person holding it would greatly increase that capacitance, hence probably making it more 'reliable'. The only alternative form of detection I can think of would be electromagnetic, but that would require current to be flowing in whatever was being tested, not just the presence of 'a voltage' (wrt earth).

Kind Regards, John

 

[EFLImpudence]

According to Fluke -

A volt stick senses the steady state electrostatic field produced by ac voltage.

How does that work for a terminated line conductor not connected to anything?
E.g. in an open switch.

 

[EFLImpudence]

Ah - great minds or fools seldom?

 

[JohnW2]

According to Fluke - A volt stick senses the steady state electrostatic field produced by ac voltage. How does that work for a terminated line conductor not connected to anything? E.g. in an open switch.

As we've both said/implied, it could not detect an electromagnetic field unless there were some current flowing (since, in the absence of current, there would be no such field to detect.

An electrostatic field (which is what you say Fluke are talking about) is a different kettle of fish, not requiring any current to be flowing (the clue is in the '-static' ) - but exactly what sort of sensor could they use to detect that? I may be out of my technological depth here! Anyone?

Kind Regards, John

 

[Jackrae]

This is better than an edition of QI

So, you are standing outside the shower, the fittings are dry and there is no indicated volts. You remain outside the shower but when the walls and fittings are wet there are indicated volts. This might suggest the volts are coming up the drain line. I'm edging back to my original hypothesis of ground generated voltage via the drain water - but I admit that sounds crazy.

Was the room light (that seems to cause the problem) ON or OFF during the video.

Just to eliminate (or add to the clues) can you apply your tester to the earth wire that runs from your DNO cut-out connection to your consumer unit. A video of you doing that might be useful.

 

[TheGovernor]

I just checked the details of the guy who came out last night, he is NAPIT registered to Electrical Inspector level, which I think is the top certification?

Would still like to know if I can usefully use my multimeter for anything too?

 

[TheGovernor]

This is better than an edition of QI

So, you are standing outside the shower, the fittings are dry and there is no indicated volts. You remain outside the shower but when the walls and fittings are wet there are indicated volts. This might suggest the volts are coming up the drain line. I'm edging back to my original hypothesis of ground generated voltage via the drain water - but I admit that sounds crazy.

Was the room light (that seems to cause the problem) ON or OFF during the video.

Just to eliminate (or add to the clues) can you apply your tester to the earth wire that runs from your DNO cut-out connection to your consumer unit. A video of you doing that might be useful.

Hi Jackrae As much as I like a mystery, this one is a bit painful...

During the video the bathroom light was on, but this morning when I did the tests I listed out, I switched the light off and it had no effect, with the light off voltage still appeared to be detected.

However, when the upstairs light circuit was switched off at the CU the detector didn't light, as soon as the circuit was made live again, it lit.

[Edit] Sorry just caught your edit. This is where I show my ignorance, what did you want me to test my volt-pen against? I'm not sure what a DNO cut out connector is?

 

[JohnW2]

This is better than an edition of QI

It is, and I really hope that we end up with an answer - otherwise I might have to pull the rest of my hair out!

So, you are standing outside the shower, the fittings are dry and there is no indicated volts. You remain outside the shower but when the walls and fittings are wet there are indicated volts. This might suggest the volts are coming up the drain line. I'm edging back to my original hypothesis of ground generated voltage via the drain water ...

Maybe ... but how would the drain line affect the shower, a few feet above?

- but I admit that sounds crazy.

I wouldn't worry about that - I don't think it's possible to postulate any explanation which doesn't sound crazy but, sooner or later', one of these 'crazy' theories is probably going to prove to be the correct one!

Kind Regards, John

 

[Jackrae]

Water had been sprayed on the fitting, run down the wall, into the drain and hence produced a completed fluid "circuit" - maybe.


edit :

Come to think of it, maybe the drain outlet (is it metal or plastic) is bonded to earth and the lines to the control valve are not - and are picking up capacitive coupling from the lighting circuit.

edit 2 :

Ignore the edit since it doesn't account for the fittings needing to be wetted

 

[JohnW2]

Water had been sprayed on the fitting, run down the wall, into the drain and hence produced a completed fluid "circuit" - maybe.

As you say, 'maybe', but I think credibility is probably getting stretched!

edit : Come to think of it, maybe the drain outlet (is it metal or plastic) is bonded to earth and the lines to the control valve are not - and are picking up capacitive coupling from the lighting circuit. edit 2 : Ignore the edit since it doesn't account for the fittings needing to be wetted

Notwithstanding your withdrawal of the first edit, what 'control valve' did you have in mind - a motorised valve in DHW plumbing, perhaps?

Kind Regards, John

 

[TheGovernor]

Water had been sprayed on the fitting, run down the wall, into the drain and hence produced a completed fluid "circuit" - maybe.

I understand the logic, if nothing else

edit :

Come to think of it, maybe the drain outlet (is it metal or plastic) is bonded to earth and the lines to the control valve are not - and are picking up capacitive coupling from the lighting circuit.

The drain outlet in the shower tray you mean? Would anyone normally put an earth to something like that?

JUst bear in mind, I've felt the effect in my wifes shower also, although I couldn't get the same result with my volt pen today...

[Edit] Thinking about it, if your theory turned out to be correct, presumably if I run the taps in the sink I should see a similar result in my tests?

edit 2 :

Ignore the edit since it doesn't account for the fittings needing to be wetted

IN terms of the DNO I worked it out using Google, video below, but to be honest I don't think it tells us much?

http://youtu.be/xfDQyrt5fsE

 

[scousespark]

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.

 

[Jackrae]

Govenor,

Humour us

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

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.

 

[333rocky333]

I am interested to find out if the LED pen (middle picture) registers (lights) a voltage as it requires a direct contact with a conductor.

No they dont i can hold mine by the screwdriver end, wave the centre body near a conducter and it will light

 

[EFLImpudence]

Yes, they do.

Your method is suppose to detect microwave leakage.