Very spooky weird electric problem

[Hopefuldave]

With AC there is no live and neutral per se.
They both spend an equal amount of time being the other.

Shouldn't be! Neutral should be at (ideal world) 0 volts relative to earth. The Neutral is tied to earth, just not at the socket in the wall - in suburban/city areas the 3-phase transformers at substations have the star neutral earthed, when it arrives at the house/factory/shop/whatever the local earth and neutral are usually bonded before the meter. Earth spikes and electrodes seem to have dropped out of fashion, shame because I've been places where all the internal metalwork (stainless sinks etc.) has been nicely bonded to Wiring Regs but there's been a fault on the local substation transformer that's pulled neutral 100v away from earth - exciting when you wash your hands under the outside tap...

Dave H. (the other one)

 

[KimB]

I am totally baffled.
We just had a thunder storm pretty close. Electric went off for about 10 seconds.
When it came back as usual the TV and amp come on along with the nvidea shield.
Thought it would be a good idea to turn off the 6 way trailing socket. It has surge protection.
Turned it off at the wall.
Another lightening strike. Power off then back on.
Went into living room. TV and amp etc switched on and running. Neon illuminated on 6 way. Switch off on wall .
How the hell???
Pulled plug out of wall.
I thought maybe contacts had fused in switch but it's fine now.
HOW????

It’s the only explanation

 

[brightspark]

I meant it doesn't really matter which way around they go. Makes no difference on AC.

it does using single pole sockets and breaking just the live . and if crossed polarity the mcb will not trip being in the now neutral feed and the wiring live feed being unprotected it dont bear thinking about

 

[Other Daniel]

So why, then, with European style plugs, it doesn't matter which way round you plug
them in ?
The supposed live and neutral are arbitary.

 

[Barking Mat]

So why, then, with European style plugs, it doesn't matter which way round you plug
them in ?
The supposed live and neutral are arbitary.

I think the idea is when you switch off the plug (in France ?) the live phase is off, I rightly or wrongly think of the neutral as the return, like a negative in DC.

You may have a powerfeed to whatever, but without a 'return', it won't work.

I.e. If the phase and neutral are reversed, the neutral is cut so your whatever won't work, but if you stick your fingers in it the phase will probably try to go through you.

Hence nowadays MCB's are double pole, as opposed to the old single feed fuse modules.

Does that make sense ?

 

[Other Daniel]

I think the idea is when you switch off the plug (in France ?) the live phase is off, I rightly or wrongly think of the neutral as the return, like a negative in DC.

You may have a powerfeed to whatever, but without a 'return', it won't work.

I.e. If the phase and neutral are reversed, the neutral is cut so your whatever won't work, but if you stick your fingers in it the phase will probably try to go through you.

Hence nowadays MCB's are double pole, as opposed to the old single feed fuse modules.

Does that make sense ?

I think I maybe understand where you're coming from, but you've still managed
to confuse me further than my originally confused state.

 

[Olderisbetter]

You will need a young priest and an old priest to preform an exorcism

 

[daleyd]

The load (what you plug in) doesn’t really care, but the supply in the circuit has to be wired correctly ie all positives connected together and all neutrals connected together. It happens that we use a fuse in our plugs on the live side and other countries don’t, but in reality you could wire a plug the opposite way (though I probably wouldn’t recommend it) and it would work perfectly ok. (For most things)…

 

[Dave-sparks]

The likey answer is either that the switch contacts remained closed despite the position of the rocker, or you didn't quite push it all the way to the off position and the contacts stayed closed.
Removing the plug would have given it enough of a nudge for the contacts to open and normal operation to resume.

 

[chunkolini]

Entropy? a being carries energy it is a form of electromagnetic energy
The world is overpopulated, this has led to a 'Soul Glut' all these traitor souls are carrying energy it has to go somewhere.
William Burroughs has the facts, why did nobody ever listen to him?

 

[MattF]

Your missus switched it on, to make you think you're going nutty?

 

[JMS1972]

So why, then, with European style plugs, it doesn't matter which way round you plug
them in ?
The supposed live and neutral are arbitary.

Three pin Euro plugs can only go into the socket one way. They have an earth connection.

Some appliances are double insulated and therefore not earthed. So have two pin plugs which can go into the socket either way.

 

[no idea]

The way I've understood it is that the neutral is nominally at 0v (same as earth) and the voltage on live is relative to neutral. Before RCDs were common, things would work if only the earth and live were used since you still got a voltage on the live relative to earth. If neutral and live are swapped, on something like a motor for example, the body of the motor would end up being connected to live (i.e. at 230v) so you've got a real risk of getting a shock.

 

[Munkul]

I don't know why we bother with live and neutral. In Europe it's just 2 pins doesn't matter which way around on AC.

Incorrect reasoning. It still matters!

In a European 230v socket they still have live, neutral, and earth (where needed)
The difference is in the appliances... MOST single phase appliances do not care which way around they are wired. Take a single phase motor. It won't reverse direction if the live and neutral are reversed.
Therefore, the plugs themselves can reverse direction... it doesn't matter to the appliance as it still will see the +ve and -ve sides of the sine wave.

We decided years ago that we wanted all appliances to use the live and neutral the same way, so the wire colours would be consistent always. So the blue should ALWAYS be neutral and therefore 0v.

Whether it's truly important I don't know... you still get sparkies that don't manage to work with 3 wire colours correctly...

 

[brightspark]

Whether it's truly important I don't know... you still get sparkies that don't manage to work with 3 wire colours correctly...

a lot cant work out the harmonised colours on 3 phase 4 core cables. even on single phase bathroom timer fans brown black and grey cables they use the black as the neutral normaly the black is the switched live sleeved with brown sleeving and the grey the neutral using blue sleeving

 

[fizzy]

The last few high bays I changed had yellow, black and earth!

 

[brightspark]

The last few high bays I changed had yellow, black and earth!

yes they used to use red singles for live feeds and yellow for the switched wires. a school i do loads of work at is wired with it . real handy when your adding wiring or altering stuff saves a load of testing to identify feeds