Shock off Neutral?

[thornton_chris]

I've always wondered if I could get a shock off of a Neutral terminal?

I understand that Neutral is connected to Ground somewhere along the way (presumably at the power/sub station) so if I touch the neutral side of an exposed wire will I get a shock? Does it make a difference if the appliance is on/off?

Cheers,

Chris

 

[Lectrician]

In a normal, functioning circuit, with the appliance on or off, you will not recieve a shock from a neutral.

In a PME / TN-C-S earthing system, which is a typical type of supply, the neutral in generally tied down to earth as often as possible en-route to your home. In the other earthing systems, the neutral is certainly tied to earth at the substation.

So, can you get a shock.....?

YES. in certain conditions.

If the neutral ever goes open circuit, it will rise to or near the mains line voltage. The 'neutral' side of the break will remain at 0v, but the other side will be deadly.

Also, the neutral can rise in volts slightly from true mother earth (the ground) due to current flowing in the conductor, creating volt drops. This slight voltage diference gives a potential which could give a 'percieved shock'. Not enough volts to do any damage, but enough to make you jump. This is not often seen, but does exist more than people think.

 

[thornton_chris]

Thanks for your superb reply. Informative, quick and to the point. Much better than all the banter I was expecting!
Thanks again.
Chris

 

[ban-all-sheds]

You can also get a shock from a neutral conductor in a borrowed neutral situation....

 

[pdcelec]

you can get a shock from a neutral if it aint connected into the neutral terminal and the phase conductor is live

 

[plugwash]

You can also get a shock from a neutral conductor in a borrowed neutral situation....

Indeed, that is basically a variant of the broken neutral sitation with the difference being that you introduce the break deliberately thinking that you have isolated adequately (when in fact you haven't because of the borrowed neutral).

When working in an unfamiliar property there is a lot to be said for isolating at least all lighting circuits before beggining any lighting work.

 

[tim west]

Ah but Holmes is it still a neutral when not connected into the neutral block

 

[IJWS15]

If the installation is not wired correctly you can.

I did and there is a photo in the hall of shame to record the cause.

 

[Taylortwocities]

Which is why the neutral is defined as a 'live' conductor.