Warning: I got sloppy.

[JBR]

I wonder 'how live' they really were? You previously wrote:
Those 'pen things that everyone on here dislikes' are quite capable of 'detecting voltage' even when there is no conductive connection to a source of electricity.

Kind Regards, John

Yes, I'm aware of what people think of them, and I can see the sense in that. However, when I had turned off the circuit breaker the 'pen thing' did not light up. Afterwards, when I turned on the CB again, it did.
I also tested using a 'mains tester screwdriver', which I know are equally disliked! That gave the same results.
I will now also admit something else I did, and some will tell me I was stupid. Having checked for live and having extracted the cable I brushed my finger against the bare end of the conductor just to be sure! Yes, I know! I was wearing rubber soled shoes standing on carpet and ensured I wasn't touching anything else, not even the wall.
You'd be quite right to tell me that I'm an idiot, but at least I'm still here.
I've put on my tin hat and am prepared for the onslaught!

 

[John D v2.0]

I brushed my finger against the bare end of the conductor just to be sure!

Could have licked it, works well for 9v batteries

 

[JohnW2]

Yes, I'm aware of what people think of them, and I can see the sense in that. However, when I had turned off the circuit breaker the 'pen thing' did not light up. Afterwards, when I turned on the CB again, it did. ... I also tested using a 'mains tester screwdriver', which I know are equally disliked! That gave the same results.

Fair enough but, as you presumably know, that does not necessarily prove very much. It's quite possible that 'stray coupling' (e.g. between cables, or switch contacts) will result in those things lighting up when the circuit as a whole is energised, but not when it's not, even if there is no 'coipper connection' between live/line and what one is testing.

I will now also admit something else I did, and some will tell me I was stupid. Having checked for live and having extracted the cable I brushed my finger against the bare end of the conductor just to be sure! Yes, I know! I was wearing rubber soled shoes standing on carpet and ensured I wasn't touching anything else, not even the wall. You'd be quite right to tell me that I'm an idiot, but at least I'm still here.

Few of us have never been known to do stupid things, so I won't dwell on what you already know about the wisdom of what you did! However, what did you feel - was it a 'significant' shock?

One has to say that, even with a standard (high impedance input) multimeter, one can often get similarly misleading results due to 'induced/coupled' voltages - to be sure that detected voltage is 'real', one either needs a low-impedance (e.g. very old-fashioned and analogue) meter or else to put a small load (like a light bulb) across the meter.

Kind Regards, John

 

[conny]

Are all electricians aware that if you receive an electric shock during the course of your employment it's mandatory, (according to our H&S), to go to hospital for an ECG?
Seems you can suffer from delayed effects and it can cause unnoticeable heart rhythms which the ECG would detect.

 

[John D v2.0]

electric shock should indeed be taken seriously, and that's presumably the idea of that regulation. However the H&S policies of your company are presumably down to their risk assessment so electricians not employed by them may not have the same policy.

 

[JohnW2]

electric shock should indeed be taken seriously, and that's presumably the idea of that regulation.

Indeed, but the reality is that the chance of an ECG picking up anything in a person who does not have any post-shock symptoms is exceedingly small, so I suspect that it is more of a local (employer's) 'CYA rule' than anything else.

Kind Regards, John

 

[JBR]

Few of us have never been known to do stupid things, so I won't dwell on what you already know about the wisdom of what you did! However, what did you feel - was it a 'significant' shock?

Actually, I never felt a thing.
I wouldn't have done it if I wasn't sure the power was off!

 

[ban-all-sheds]

So why did you do it?

I wouldn't have done it if I wasn't sure the power was off!

I brushed my finger against the bare end of the conductor just to be sure!

https://en.wikipedia.org/wiki/Cognitive_dissonance

 

[JBR]

So why did you do it?
https://en.wikipedia.org/wiki/Cognitive_dissonance

An interesting article. Thank you.

I can justify my actions as follows. If I had been wrong and the conductor had, in fact, been live, by quickly brushing my finger past the end I would have received a very brief (and hopefully mild as I was sure I was well insulated) shock. Had I not taken that precaution and handled the conductors more firmly (and in so doing made unintentional contact elsewhere at the same time) the consequences could have been far more serious.

 

[ban-all-sheds]

I can justify my actions as follows. If I had been wrong and the conductor had, in fact, been live

But you said you could not have been wrong

I wouldn't have done it if I wasn't sure the power was off!

by quickly brushing my finger past the end I would have received a very brief (and hopefully mild as I was sure I was well insulated) shock.

Would it surprise you to learn that is about as far from a recognised technique for proving dead as it is possible to get, and utterly bonkers?

 

[JBR]

But you said you could not have been wrong

Would it surprise you to learn that is about as far from a recognised technique for proving dead as it is possible to get, and utterly bonkers?

I said I was sure, but even though I was sure it is conceivable that I was wrong.

No, I accept it is not a recognised technique for proving dead, but I thought it preferable to handling the conductor more firmly.

 

[rsgaz]

I would have received a very brief (and hopefully mild as I was sure I was well insulated) shock.

No, you wouldn't. You would have felt nothing at all. As you were insulated and not touching anything else, you don't feel anything at all. In the same way that birds can land on 400kv lines and don't even notice it.

I'm certainly not recommending that people go and try it!! But nothing actually happens if you are not making a circuit.

 

[ban-all-sheds]

In the same way that birds can land on 400kv lines and don't even notice it.

 

[JBR]

No, you wouldn't. You would have felt nothing at all. As you were insulated and not touching anything else, you don't feel anything at all. In the same way that birds can land on 400kv lines and don't even notice it.

I'm certainly not recommending that people go and try it!! But nothing actually happens if you are not making a circuit.

I have to disagree, through personal experience. As a young child, I once touched the small serrated wheel at the end of an electric fire element, thinking I could turn it. The fire was turned off, but must have been wired incorrectly.
I was kneeling, clothed, on a carpet and was not touching anything else, but received a bit of a belt - enough to put me off doing that again, anyway.

Similarly, and much more recently, I have lightly run my fingers along the metal upright of a standard lamp which I assumed was earthed and felt what I thought was a slight 'vibration' or 'roughness'. Induced voltage, I believe.

I'd be very surprised not to have felt anything as the body has a certain capacitance but, of course, you may be right.

 

[JBR]

On reflection, perhaps I could have touched the two conductors together. That would have shown whether they were still live!