In that diagram I was referring to the wire labelled B as live, in that if you held on to it and were earthed you would get a shock, but it seems that electricians would not refer to it in that fashion.
Yes, you would be right.
Technically the neutral wire is also a 'live' conductor but not a 'line' conductor.

That is why the everyday use of live and neutral is confusing - but that is how people refer to it.

However, frequently people call the two wires at a switch live and neutral, solely because one is red and one is black (or brown and blue).

Doesn't France use switched neutrals?

I have no idea. As it's dangerous, quite possibly . However, we are not in France, so that's not relevant.

He said the lamp limits the current going from switched live to neutral? By which I read the current drawn at switched live is lower than the current at neutral.
Fair enough - but that is clearly a total misunderstanding of what bernard was saying, and also suggests a lack of understanding of what an electrical circuit is.

Unless there is some other path available (like a 'leak to earth' through a fault) the current in the switched live and neutral must always be the same, since the current has 'nowhere else to go'.

If you limit the flow of water going through a hosepipe by, say, standing on it, then the flowing coming from the water source and the flow coming out of the end of the hose will inevitably be the same, since the water has 'nowhere else to go'

Kind Regards, John

Live--------Switch-----Lamp-------Neutral

To be blunt if you cannot understand that there is no direct connection between Live ( or switched Live ) in the lamp to Neutral then your understanding of basic electrics is inadequate for you to do any work on electrical equipment.
Thanks for trying to help.

Which (as well as being unnecessarily rude) seems to me to be nonsense.

Presumably Bernard means something different by some of these words.

Now I'm going to be very blunt. Until now I've avoided joining in as I would have been making comments similar to bernards much earlier.

A list of proficient and competent people have all described EXACTLY the same thing using different words in the hope that each in turn is able to HELP you.

Please do not insult their totally correct assistance.

Doesn't France use switched neutrals?
I don't know, but it seems unlikely - I can't think of any advantage, so I don't see why they should choose the dangerous approach rather than the safer one.

Kind Regards, John

So explain why the "piece of wire " in the incandescent bulb glows white hot yet the other pieces of wire do not even get warm.
Perhaps you would first explain why that piece of wire is not a "direct connection between Live ( or switched Live ) in the lamp to Neutral".

Advice that is given to try and prevent accidents can seem to be rude.
The same idea can be expressed in numerous different ways. Using a rude option rarely achieves the best results.

Yes, you would be right.
Thanks for the confirmation.

Now I'm going to be very blunt. Until now I've avoided joining in as I would have been making comments similar to bernards much earlier.

A list of proficient and competent people have all described EXACTLY the same thing using different words in the hope that each in turn is able to HELP you.

Please do not insult their totally correct assistance.
Despite never having met you I have quite a lot of respect for you, as you come across as a very reasonable & helpful person. However I have to disagree with you here.

What was said may have come across to you as clear but it was not clear to me.

It was only when I read @EFLImpudence post (15) and responded to it that I worked out that the wire labelled B in my diagram (in post 20) is live in the sense of being at 240V but would not be called live by electricians. Up until then we had been talking at cross purposes - I had been talking about (what you would call) a switch in the neutral wire as a switch between live & neutral.

So no matter how it was phrased, until I understood how that wire B was viewed by you I could not understand what was meant.

I don't know, but it seems unlikely - I can't think of any advantage, so I don't see why they should choose the dangerous approach rather than the safer one.

Kind Regards, John
My very limited experiencce of working in France found only double pole MCB's and switches. Interestingly red = line, blue = neutral & yellow or purple = switched line whereas the power circuits were black/blue [220], black/orange [380 2 phases]. red/orange or yellow/black or blue [380 3phase]plus blue neutral - (note italics match our older colours), white/white [440v split phase]. It was an older commercial property and we had strict instructions to maintain the existing colours [as per regs?] rather than use the latest selection and create confusion.

Fair enough - but that is clearly a total misunderstanding of what bernard was saying, and also suggests a lack of understanding of what an electrical circuit is.

Unless there is some other path available (like a 'leak to earth' through a fault) the current in the switched live and neutral must always be the same, since the current has 'nowhere else to go'.

If you limit the flow of water going through a hosepipe by, say, standing on it, then the flowing coming from the water source and the flow coming out of the end of the hose will inevitably be the same, since the water has 'nowhere else to go'

Kind Regards, John

In your opinion. If I read it as saying something else, then I read it as saying something else. Tough!

Perhaps you would first explain why that piece of wire is not a "direct connection between Live ( or switched Live ) in the lamp to Neutral".

The same idea can be expressed in numerous different ways. Using a rude option rarely achieves the best results.

Thanks for the confirmation.

Despite never having met you I have quite a lot of respect for you, as you come across as a very reasonable & helpful person. However I have to disagree with you here.

What was said may have come across to you as clear but it was not clear to me.

It was only when I read @EFLImpudence post (15) and responded to it that I worked out that the wire labelled B in my diagram (in post 20) is live in the sense of being at 240V but would not be called live by electricians. Up until then we had been talking at cross purposes - I had been talking about (what you would call) a switch in the neutral wire as a switch between live & neutral.

So no matter how it was phrased, until I understood how that wire B was viewed by you I could not understand what was meant.
Hi Stephen. First of all thanks for the compliment, I'm not convince all on here will agree.

We come to this site primarily to offer advice for safety. (I tried to make that a massive full stop!)

We are basically giving away free advice which is taking money away from our earning ability, which I'm sure you will agree is a rather silly thing to do.

When people ask for help, our first requirement is to do a health and safety risk assessment, that is automatic to the point we may not actually realise we're doing it.
We need to ensure the person asking for help has sufficient knowledge and then we need to attempt to assess the posters practical abilities and offer some (very obvious to us)advice such as "no neutral at the switch" so the poster is made aware of terms/proceedures etc.

In other words we establish the poster has enough understanding of the electrics and our advice to be able to do the job properly, one only has to look at some of the pictures posted on here to see that many people that tinker have absolutely no idea what they are doing.
Frequently at around that point we'll start advising to get in a professional.

Then we start on the nitty gritty of the problem and usually manage to resolve it.

Your initial inability to follow or understand the descriptions given [all of which were in very simple terms and correct] actually makes several in the thread think you do not have enough background knowledge to be tinkering although they haven't stated it. Secondly it is very rude to then tell a seasoned professional he is wrong when he has offered perfect advice and at a lower basic level to where we would expect to be for someone working on a potentially dangerous system.
In your opinion. If I read it as saying something else, then I read it as saying something else. Tough!
In which case ask another question, don't say it's wrong.

It was only when I read @EFLImpudence post (15) and responded to it that I worked out that the wire labelled B in my diagram (in post 20) is live in the sense of being at 240V but would not be called live by electricians.
I don't think that electricians would disputer the fact that the wire B in your diagram [I take it that you mean post 26 ? ] is 'live', in the sense that (as you say),one could get an electric shock from it, but ...
... Up until then we had been talking at cross purposes - I had been talking about (what you would call) a switch in the neutral wire as a switch between live & neutral.
... which was, indeed, the problem. In terms of conductors (wires) "live" (or "line") refers to that which brings an electricity supply to a load (like a lamp) and "neutral" returns the current (from the 'other side' of the load) back to the supply.

The whole point of having switches in the Live/Line conductor, rather than the neutral, is to avoid the very danger to which you refer, in which (with a switch in the neutral) both sides of the load (lamp) will remain 'live' (in a sense that one could get a shock from them) even when the switch was 'off'.

An electrical circuit is no different from, say, a central heating system, in which a boiler+pump (analogous with the electricity supply) pumps water through a radiator (analogous to the lamp) and then, from 'the other side of the radiator', back to the pump. We would call the pipe going to the radiator the 'supply' or 'flow' pipe, and that coming from the other side of the radiator back to the boiler as the 'return' pipe. We would not dream of calling the latter the 'supply' (or 'flow') pipe, even though water (having come though the radiator) would pour out (analogous to getting an electric shock) if one cut it.

As I think has been said, it is really essential that anyone considering doing anything to an electrical installation should have at least a basic understanding of the concept of an electrical circuit.

Kind Regards, John

Hi Stephen. First of all thanks for the compliment, I'm not convince all on here will agree.

We come to this site primarily to offer advice for safety. (I tried to make that a massive full stop!)

We are basically giving away free advice which is taking money away from our earning ability, which I'm sure you will agree is a rather silly thing to do.

When people ask for help, our first requirement is to do a health and safety risk assessment, that is automatic to the point we may not actually realise we're doing it.
We need to ensure the person asking for help has sufficient knowledge and then we need to attempt to assess the posters practical abilities and offer some (very obvious to us)advice such as "no neutral at the switch" so the poster is made aware of terms/proceedures etc.

In other words we establish the poster has enough understanding of the electrics and our advice to be able to do the job properly, one only has to look at some of the pictures posted on here to see that many people that tinker have absolutely no idea what they are doing.
Frequently at around that point we'll start advising to get in a professional.

Then we start on the nitty gritty of the problem and usually manage to resolve it.

Your initial inability to follow or understand the descriptions given [all of which were in very simple terms and correct] actually makes several in the thread think you do not have enough background knowledge to be tinkering although they haven't stated it. Secondly it is very rude to then tell a seasoned professional he is wrong when he has offered perfect advice and at a very basic level to where we would expect to be for someone working on a potentially dangerous system.

In which case ask another question, don't say it's wrong.

Yes I suppose I should have asked for clarification, but I read it unambiguously as an incorrect statement.

In your opinion. If I read it as saying something else, then I read it as saying something else. Tough!
Fair enough but, as I said, I would have hoped that anyone who felt it appropriate to comment would have had enough understanding of the concept of an electrical circuit to be able to correctly read what bernard had written as saying what he meant.

I watched the John Ward video and clearly some errors.
1) The contacts in a switch/RCD/etc are independent for line and neutral and if the neutral switches without the line then the two wire testers would fail to show the supply was still live, so with a two wire tester you need to measure to an un-switched return like the earth.
2) Although the single contact or capacitive link device may not be reliable, it does detect if only the neutral has been switched in most cases, and will also with the neon screwdriver likely raise the alarm where there is a borrowed neutral.
3) You should always use a proving unit as we want to know if the voltage is above 50 volt not simply that 230 volt is not there, so the proving unit goes up in stages to show all lamps work in sequence.
4) He is correct you should not really use anything requiring batteries so the volt stick and multi-meter are considered as not safe as the batteries could go flat or have a poor connection.

I watched the proving unit shown and if it did show 50, 100 etc I did not see it show that, and it seemed two lamps did not work so that proving unit and tester clearly not matched. And with the bulb tested clearly if testing to 500 volt then say good by to the bulb.

Also he did not show testing for current flow, so either you use neon screwdriver or clamp on ammeter OK with test circuit it was clear there was no borrowed neutral but the idea was to show have to prove dead on any circuit.

Clearly if using a MCB you now the neutral is not being switched, but even then you don't know the earth or neutral is at bonded polarity, the bonded metal work does need to be tested to show no more than 50 volt between bonded metal work and earth and neutral.

I would agree with RCD protection likely if there is a fault causing bonded metal work not to be earthed then likely the RCD will trip, and unless using a TT supply it is unlikely neutral and earth are a different polarity, however he did not show checking loop impedance or any other method to ensure you know supply type, so it needs to cover all supply types.

I have found a fuse box where some one has bridged one set of contacts on the isolator, so one should really test input to output so checking each set of contacts. If everything is correct turning off the MCB labelled sockets will turn off sockets, the whole idea of proving dead if for when not wired or labelled correctly.

Are you saying that the two wires in a light switch are never L&N but always L&SL?
If the two wires at the switch were L and N, what do you think would happen when the switch was closed?

But live must connect to neutral somewhere to complete the circuit.
Live connects to one side of the load, neutral to the other side of the load; the load is placed in-between live and neutral.

So live is never connected directly to neutral, but through the load.

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