After some advice: Mild tingle from shower when in use

[JohnW2]

I told you not to try that, and my advice still holds. Even if you do have more than 1.

Do you mean don't do the pipework to true earth test ban-all-sheds?

I think BAS was referring to your "willies", which he is advising you not to use for tests

Kind Regards, John

 

[EFLImpudence]

I have placed my detector on a pile of books and walked away; it remains lit.

 

[JohnW2]

I have placed my detector on a pile of books and walked away; it remains lit.

Mr Fluke must be lying, then

What presumably matters (in terms of the mechanism they describe) is the capacitive coupling between the body of the device and earth - so, as I've suggested before, it's possible that the capacitance to earth is, in some situations, adequate just from the body of the device, without need for assistance of a human body. You might find that if you put your pile of books somewhere else (e.g. on a table), it might not work

.... either that or Mr Fluke is totally lying about how his device works! (are you sure that the explanation you linked to applies to whichever particular device you're using?)

Kind Regards, John

 

[TheGovernor]

I told you not to try that, and my advice still holds. Even if you do have more than 1.

Do you mean don't do the pipework to true earth test ban-all-sheds?

I think BAS was referring to your "willies", which he is advising you not to use for tests

Kind Regards, John

lol, had my serious head on for a minute there. To be honest fella's you're seeing a lot of the inside of my house just now, but the last thing you need to see is me using my tool for unintended purposes

 

[EFLImpudence]

(are you sure that the explanation you linked to applies to whichever particular device you're using?)

No. I just assumed they must all similar.

 

[JohnW2]

lol, had my serious head on for a minute there. To be honest fella's you're seeing a lot of the inside of my house just now, but the last thing you need to see is me using my tool for unintended purposes

Indeed! Returning to your serious question, there's no reason not to test between radiator/ pipework/ whatever and 'true earth' provided you heed bernard's warning to be careful what you touch, just in case of the incredibly unlikely possibility that your supply is L/N reversed, such that there is a 230V difference between your radiators etc. and true earth.

Kind Regards, John

 

[JohnW2]

(are you sure that the explanation you linked to applies to whichever particular device you're using?)

No. I just assumed they must all similar.

"Never assume" - although you are, of course, probably right! I think I may have to get hold of a (functioning) one of these thingies and see what I can discover - ultimately destructively, if necessary!

Kind Regards, John

 

[TheGovernor]

lol, had my serious head on for a minute there. To be honest fella's you're seeing a lot of the inside of my house just now, but the last thing you need to see is me using my tool for unintended purposes

Indeed! Returning to your serious question, there's no reason not to test between radiator/ pipework/ whatever and 'true earth' provided you heed bernard's warning to be careful what you touch, just in case of the incredibly unlikely possibility that your supply is L/N reversed, such that there is a 230V difference between your radiators etc. and true earth.

Kind Regards, John

Understood, I'm just trying to figure out what I have in the house/garage I can use as my meter probes are fairly short...

 

[JohnW2]

Understood, I'm just trying to figure out what I have in the house/garage I can use as my meter probes are fairly short...

Do you have an extension lead or extension cable reel of adequate length? If so, you could use that, together with a spare plug, to improvise a 'long test lead'.

Kind Regards, John

 

[TheGovernor]

I have got an extension lead, so you're thinking, plug the extension lead into a socket, run it within reaching distance of the rod and then take a voltage reading between the earth pin of the extension lead and the ground rod?

 

[JohnW2]

I have got an extension lead, so you're thinking, plug the extension lead into a socket, run it within reaching distance of the rod and then take a voltage reading between the earth pin of the extension lead and the ground rod?

Well, you could do that (you'd obviously have to put a plug into the socket of the extension to get access to the 'earth pin) - but that would be somewhat different from what was being suggested. If you did that, you could leave the socket (into which extension lead was plugged) switched off - but that could still present a potential danger - in that IF the socket's switch was 'single pole' and IF that incredibly unlikely L/N reversal were present, the neutral pin at the end of your extension could be 'live' (230V relative to true earth).

What I was actually thinking of was to just use the extension lead as a 'wire', not plugging it in to anything - i.e. somehow connect the earth pin of the extension's plug to the radiator, pipe or whatever, then use the earth pin (via a plug) at the other end of the extension to measure the voltage between that and your 'true earth rod'.

Kind Regards, John

 

[ban-all-sheds]

"Never assume"

Actually Gov, please assume you were right in what you said at 13:22....

 

[TheGovernor]

I have got an extension lead, so you're thinking, plug the extension lead into a socket, run it within reaching distance of the rod and then take a voltage reading between the earth pin of the extension lead and the ground rod?

Well, you could do that (you'd obviously have to put a plug into the socket of the extension to get access to the 'earth pin) - but that would be somewhat different from what was being suggested. If you did that, you could leave the socket (into which extension lead was plugged) switched off - but that could still present a potential danger - in that IF the socket's switch was 'single pole' and IF that incredibly unlikely L/N reversal were present, the neutral pin at the end of your extension could be 'live' (230V relative to true earth).

What I was actually thinking of was to just use the extension lead as a 'wire', not plugging it in to anything - i.e. somehow connect the earth pin of the extension's plug to the radiator, pipe or whatever, then use the earth pin (via a plug) at the other end of the extension to measure the voltage between that and your 'true earth rod'.

Kind Regards, John

Okay did it, I used a 6 inch screw as my rod into absolutely rain sodden grass

Got an extension, and old bit of cable and spare plug, check continuity between the radiator and the earth pin of the extension lead plug, all good.

Reading between earth pin and rod/screw was 0.2v, rising to 0.43 and back down again (seemed to coincide with wife putting on the microwave?
She likes to add variables in while I'm trying to do something!!)

Dropped back to 0.2v.

So, if I'm building a proper understanding, well within the completely acceptable range?

 

[JohnW2]

Okay did it, I used a 6 inch screw as my rod into absolutely rain sodden grass ... Got an extension, and old bit of cable and spare plug, check continuity between the radiator and the earth pin of the extension lead plug, all good. ... Reading between earth pin and rod/screw was 0.2v, rising to 0.43 and back down again (seemed to coincide with wife putting on the microwave? ... Dropped back to 0.2v. ... So, if I'm building a proper understanding, well within the completely acceptable range?

Thanks. As you say, nothing unexpected there. Some very small measured voltage is almost inevitable.

Kind Regards, John

 

[TheGovernor]

So we have :

A negligible difference between the house and true of 0.2v-0.5v

A difference between the shower waste and shower of 1.9v - 5.9v (depending on how wet it is apparently).

So if the house is only 0.5v different to earth, is it reasonable/acceptable that I'd be picking up 1.5v potential difference elsewhere within the house?

Further to that, is it reasonable/acceptable that the lighting circuit can add 4v when the shower is used?