IEC plug/socket... live vs neutral?

[KL27x]

I have 2 power cords. They plug into the 110 mains socket on one end. They have a IEC 320 C14 looking plug on the other end. The kind that goes into a 3 prong socket like you find on a monitor or computer psu, etc.

The live and neutral are wired opposite to each other on these cords. 

The only reason I noticed is because I am wiring up a transformer to an IEC socket. I picked up the nearest power cord to figure out which pin of the socket I should fuse. Later, I am testing the transformer and I notice I have it backwards. Then I see I'm using a different cord. And I find out the cords are wired differently.

Is there a standard? If so, which one do I throw out?

[Zbig]

I will evade the question by expressing my opinion that if your equipement is not live/neutral "agnostic", it's not designed properly. For instance, that's the kind of mains socket prevalent throughout many parts of Europe:



The live/neutral assignment ("polarity" if you will) depends on whether you stick the plug into the upper or the lower socket.

[KL27x]

Sure. Double-insulation and all. But if the cords are not manufactured the same way, that's just insanity. Maybe I have cords from different countries with different standards?

It bothers me because. If I wanted polarity to be random, I'd make the plug so it can be flipped. The earth pin could be directly in the middle, or what not. Then the plug could go in either way, like a figure 8 plug/socket. If it can go in just one way, it should be wired the same way every time, for sake of order, if nothing more.

[alm]

This site lists a pin-out. I am sure you could find the definite reference in IEC 60320 if you feel like paying the fees or can find a copy somewhere. Do you not have a box with a dozen of these that you could measure to figure out if there is a consistent polarity?

[magnusbh]

Hi, you have to remeber that there is no guarantee for how the wires are connected inside the wall, the only guarantee is the GND. Live and neutral has no standard in the mains socket that you could trust (even if some manufactures mark them with "N" and "L".

BR
Magnus

[drussell]

Egads!  I had no idea there were places in the world where it was random!

Certainly here in North America it is controlled (well, at least since the 1950s-60s)...  The small blade is the hot, large blade is the neutral and even simple appliances or things like lamps are wired to switch the hot so that the socket and the base of the bulb is not live when the power switch is off!

Sure, you see the occasional wall plug where they were wired backwards by someone who didn't know what the were doing... (always a dead giveaway and to me always means check every damn outlet in the house!)

For the IEC connector end, it should be like this:



If you find a cord that is wired incorrectly, I would chop it in half and discard it immediately!  I suppose if it seems to be reasonable quality (doubtful if they didn't even get the wiring polarity correct!) you could keep whichever end was wired with the proper colors. 

P.S. Zbig, are you sure that plug you show doesn't swap the terminals internally?  It seems insane to me that it wouldn't be properly marked and consistent!

[Ranayna]

Well, the plugs here in Germany definetly are not polarized:

[alm]

Given that most of the plugs that fit in the socket Zbig posted will also fit a German Schuko socket which is non-polarized, I could see how the designers of the socket might not worry too much about consistent polarization.

[drussell]

Yeah, I'm shocked!   

I just looked it up and, yeah, sure enough the Schuko and Europlug styles do not specify a line vs neutral.  Crazy! 

The giant UK style ones are specified, as are the Australian style but not the rest of Europe, apparently!  Well, well...  You learn something new every day! 

[Nusa]

This is one of those cases where not showing a country tag will affect the relevancy of the answers to the question.

[drussell]

This is one of those cases where not showing a country tag will affect the relevancy of the answers to the question.

Indeed!

I made the assumption that we were talking about North America, though, when KL27x said:

I have 2 power cords. They plug into the 110 mains socket on one end.

As an aside, I like the way the Badcaps forum has a "mains voltage and frequency" field for user profiles.

[glarsson]

I just looked it up and, yeah, sure enough the Schuko and Europlug styles do not specify a line vs neutral.  Crazy!

In my view this is a safety feature. If the safety of a lightbulb depends on all parts connecting the line and neutral correctly then the safety is easily compromised. Better to build the safety of devices without knowledge on how line and neutral are connected.

[ejeffrey]

Yeah, it is crazy.  For most applications it shouldn't matter -- grounded and double insulated appliances should treat the live and neutral equivalently.  Old appliances that connect neutral to the frame (!) or are not double insulated by designed so that a single fault connects the neutral to the frame are really obsolete.  But there are still cases out there such as Edison light sockets and exposed heating elements in toasters where putting the less dangerous terminal towards the user makes sense, and lack of consistent polarization of outlets is not really what you want.  But in most of Europe that is what you have.

Worse yet, the shucko and similar plugs are designed so that they will mate with non-grounded outlets, which are common and AFAIK, actually still code compliant in some European countries for new residential wiring in dry rooms.  This is total madness, and compared to that, the polarized plug thing is a minor detail.

[ejeffrey]

I just looked it up and, yeah, sure enough the Schuko and Europlug styles do not specify a line vs neutral.  Crazy!

In my view this is a safety feature. If the safety of a lightbulb depends on all parts connecting the line and neutral correctly then the safety is easily compromised. Better to build the safety of devices without knowledge on how line and neutral are connected.

As long as you use Edison light sockets, that is impossible.  A major point of a polarized plug is that the outer shell of the lamp is supposed to be neutral, and the hot wire is recessed and much harder to accidentally contact.

[alm]

Fixed light sockets should be installed with neutral to the screw thread. And other lamps should be unplugged before changing the bulb. I agree that this is one of the (old) connectors where polarization would improve safety, but for any new design hot and neutral polarity should not affect safety. What if your device is used on a ship that might have both wires hot and no neutral?

As for the grounded plugs in ungrounded sockets, what else are you going to do with a large installed base of ungrounded sockets? Tell people they are not allowed to buy modern appliances? Replace the electrical systems everywhere? It would probably only slightly less painful than switching the US to 230 V/50 Hz.

[hermit]

For most applications it shouldn't matter

If it has an on/off switch it matters.  You switch the hot side so nothing is live on the other side.

[glarsson]

If it has an on/off switch it matters.  You switch the hot side so nothing is live on the other side.

No. The switch should switch both wires.

[alm]

You switch the hot side so nothing is live on the other side.

That is a dangerous assumption. You should always unplug something if you are going to service it. If you are not, what do you care that some wires inside the appliance are hot? It is not like any current is going to flow.

[hermit]

If it has an on/off switch it matters.  You switch the hot side so nothing is live on the other side.

No. The switch should switch both wires.

Well, you are free to implement what you want, but this isn't how it is done in the real world.  Neutral eventually ties back to Earth ground so if you switch it out you are disabling a potential safety.

[RGB255_0_0]

If it has an on/off switch it matters.  You switch the hot side so nothing is live on the other side.

No. The switch should switch both wires.

Well, you are free to implement what you want, but this isn't how it is done in the real world.  Neutral eventually ties back to Earth ground so if you switch it out you are disabling a potential safety.

Not always.

[hermit]

You switch the hot side so nothing is live on the other side.

That is a dangerous assumption. You should always unplug something if you are going to service it. If you are not, what do you care that some wires inside the appliance are hot? It is not like any current is going to flow.

I simply stated what is normally considered 'code'.  It has nothing to do with repair and everything to do with what can happen while it is sitting there doing nothing.  Having live current in an an otherwise idle device can do many things and probably most of them are bad.  That is why you switch the hot side.  If wired correctly the neutral side can act as Earth ground.  Which side would you switch?

[RGB255_0_0]

If wired correctly the neutral side can act as Earth ground.

[hermit]

Not always.

Not always WHAT?  Please not the use of the word "potential" in my post.  My job is not code enforcement but it is to know what the code is.

[hermit]

If wired correctly the neutral side can act as Earth ground.

Ah.  Now I get it.  Trolling.  I was there when the electrician installed my new panel.  I can assure you my neutral is correctly installed and is tied to ground.  If you want to ignore the totality of a posting please just ignore it all.

[Tepe]

Not always.

Not always WHAT?  Please not the use of the word "potential" in my post.  My job is not code enforcement but it is to know what the code is.

I guess the point was that the code differs with geography.

[Nusa]

Remember this is an international forum. Every country or region has its own code, and it's not necessarily compatible with the code you know.

Regardless, making assumptions is dangerous. Don't assume the device is correct. Don't assume the wall outlet is correct. Unless you've personally checked it. Unplugging the device before opening it up is a generally smart thing to do.

[RGB255_0_0]

If wired correctly the neutral side can act as Earth ground.

Ah.  Now I get it.  Trolling.  I was there when the electrician installed my new panel.  I can assure you my neutral is correctly installed and is tied to ground.  If you want to ignore the totality of a posting please just ignore it all.

Link the part that says you can use the neutral to act as Earth ground.

[hermit]

If wired correctly the neutral side can act as Earth ground.

Ah.  Now I get it.  Trolling.  I was there when the electrician installed my new panel.  I can assure you my neutral is correctly installed and is tied to ground.  If you want to ignore the totality of a posting please just ignore it all.

Link the part that says you can use the neutral to act as Earth ground.

Again, selective reading on your part. It is all laid out in what I have posted.  But, let's pretend you aren't trolling.  If you are designing a product that needs to be switched on and off, which side would you switch and why? 

[Gyro]

It all seems pretty messy from the comfortable viewpoint of the UK. 

I know that products these days shouldn't care, but there's still a warm and fuzzy feeling about always having the fuse in the Live.

[hermit]

It all seems pretty messy from the comfortable viewpoint of the UK. 

I know that products these days shouldn't care, but there's still a warm and fuzzy feeling about always having the fuse in the Live.

No.  If they are switched they do care.    The switch is on the live for the same reason your warm fuzzy feeling fuse is.  Would you put the fuse on the ground side?

[newbrain]

Once again: there might not even be a neutral at all.
I learned about it at the university, since I lived in areas where both wires were hot, and thought that was the normal case.

And, when I'm in Italy, that's still the case, though the building is decently new and has been brought up to "code".

Never ever assume what's behind a wall socket.

[Tepe]

Would you put the fuse on the ground side?

Ground side? I'll assume you meant neutral.
Take a good look at that German Schuko outlet in the picture further up and think again.

[hermit]

Would you put the fuse on the ground side?

Ground side? I'll assume you meant neutral.
Take a good look at that German Schuko outlet in the picture further up and think again.

Obviously the discussion applies to systems that are polarized (define hot/neutral).  There is good reason to have polarized systems, safety is one.  In the US two wire gave way to 3 wire for a reason.

[glarsson]

Well, you are free to implement what you want, but this isn't how it is done in the real world.

Perhaps not in your world, but on our side of the pond it is common.

Polarized sockets and single wire switching (your world) or unpolarized sockets and double wire switching (my world).

[Tepe]

Would you put the fuse on the ground side?

Ground side? I'll assume you meant neutral.
Take a good look at that German Schuko outlet in the picture further up and think again.

Obviously the discussion applies to systems that are polarized (define hot/neutral).  There is good reason to have polarized systems, safety is one.  In the US two wire gave way to 3 wire for a reason.

Apparently large parts of Europe has chosen not to have polarized outlets and sockets even when using three wires and it would probably be a rare appliance that is designed solely to be used with polarized UK plugs in mind.

[SeanB]

Design rules for appliances are always going to be slightly schizophrenic. They call for both active and return ( or live and neutral) conductors to have equal insulation on them, and that they should both be treated as being live conductors. Then the same regulations say that you should not fuse the neutral, and that there should not be a switch in the neutral side ( double pole switches that are designed to safely switch both conductors are allowed though) in this. Non polarised mains calls for fusing of both active conductors, and for for a switch that is either single pole or double throw. Hard to reconcile them both in a product made for a world market, unless you have 2 versions.

[Benta]

Design rules for appliances are always going to be slightly schizophrenic. They call for both active and return ( or live and neutral) conductors to have equal insulation on them, and that they should both be treated as being live conductors. Then the same regulations say that you should not fuse the neutral, and that there should not be a switch in the neutral side ( double pole switches that are designed to safely switch both conductors are allowed though) in this. Non polarised mains calls for fusing of both active conductors, and for for a switch that is either single pole or double throw. Hard to reconcile them both in a product made for a world market, unless you have 2 versions.

You're mixing up appliances and installations. There is no disconnect in the codes.

For appliances, it makes perfect sense to treat live and neutral the same, as in some areas of the world the plug can be rotated 180 deg without problem, and also, you never know which dork changed the plug at some point.

For installations, it's a different story, as they should be done by professionals, and switching and fusing only the live makes sense to avoid a ton of copper in the house.

[hermit]

Well, you are free to implement what you want, but this isn't how it is done in the real world.

Perhaps not in your world, but on our side of the pond it is common.

Polarized sockets and single wire switching (your world) or unpolarized sockets and double wire switching (my world).

In the US, residential power is 240V single phase with a grounded center tap on the transformer.  That center tap is what we call neutral.  Most of Europe seems to be 230V.  I can't find a transformer configuration to confirm your 'neutral'.  Indeed, it would explain the double pole switch and lack of polarization at the plug.  Here we have a similar requirement because both legs would be considered 'hot'.  I guess we need to make sure we are talking about the same thing here. 

[glarsson]

In the US, residential power is 240V single phase with a grounded center tap on the transformer.  That center tap is what we call neutral.  Most of Europe seems to be 230V.  I can't find a transformer configuration to confirm your 'neutral'.  Indeed, it would explain the double pole switch and lack of polarization at the plug.  Here we have a similar requirement because both legs would be considered 'hot'.  I guess we need to make sure we are talking about the same thing here.

The common installation here in Sweden is 230V three phase, neutral and ground arriving at the house (230V between phase and neutral, 400V between phases). Installations in the house is either three phase for some appliances (stove, heater) and single phase for normal outlets and lights (split over the three phases). Fuses and switches on the live side only. Outlets are non polarized (German Schuko). Most home appliances are double insulated and most likely witch both leads.

[ejeffrey]

I simply stated what is normally considered 'code'.  It has nothing to do with repair and everything to do with what can happen while it is sitting there doing nothing.  Having live current in an an otherwise idle device can do many things and probably most of them are bad.  That is why you switch the hot side.  If wired correctly the neutral side can act as Earth ground.  Which side would you switch?

If, as you say, your job is to know what the code is and you say that "neutral can act as earth ground" you are terrible at your job.  There is nothing in modern US code that says you can ever treat neutral as ground or safe.

Yes, it is normal and allowed to only switch the live wire on polarized equipment.  But double insulated equipment can and does switch both side (if it has a switch at all).  That does not mean that "neutral side can act as ground" which that is a dangerous, irresponsible, and incorrect thing to say.

[Benta]

In the US, residential power is 240V single phase with a grounded center tap on the transformer.  That center tap is what we call neutral.  Most of Europe seems to be 230V.  I can't find a transformer configuration to confirm your 'neutral'.  Indeed, it would explain the double pole switch and lack of polarization at the plug.  Here we have a similar requirement because both legs would be considered 'hot'.  I guess we need to make sure we are talking about the same thing here.

The common installation here in Sweden is 230V three phase, neutral and ground arriving at the house (230V between phase and neutral, 400V between phases). Installations in the house is either three phase for some appliances (stove, heater) and single phase for normal outlets and lights (split over the three phases). Fuses and switches on the live side only. Outlets are non polarized (German Schuko). Most home appliances are double insulated and most likely witch both leads.

I concur with everything here, that's how installations are made within the EU. I disagree with the last few words, though, mostly just one lead is switched. The assumption is, that noone would be crazy enough to change a bulb or a fuse without unplugging the device first. But even if you do, you'd have to stick in your fingers a long way to get injured.

[hermit]

I simply stated what is normally considered 'code'.  It has nothing to do with repair and everything to do with what can happen while it is sitting there doing nothing.  Having live current in an an otherwise idle device can do many things and probably most of them are bad.  That is why you switch the hot side.  If wired correctly the neutral side can act as Earth ground.  Which side would you switch?

If, as you say, your job is to know what the code is and you say that "neutral can act as earth ground" you are terrible at your job.  There is nothing in modern US code that says you can ever treat neutral as ground or safe.

Yes, it is normal and allowed to only switch the live wire on polarized equipment.  But double insulated equipment can and does switch both side (if it has a switch at all).  That does not mean that "neutral side can act as ground" which that is a dangerous, irresponsible, and incorrect thing to say.

Again, someone that wants to pull a few words out of context to prove their point.  If I go into my basement and find my circular saw half submerged in water from overnight flooding you are telling me the neutral CANNOT be acting as ground because that would be a "dangerous, irresponsible" thing for it to be doing?   

Maybe I should fire the electrician that tied my neutral to ground at the box and then proceeded to jump my water meter to make sure it had a path to ground.  Not only that he proceeded to run an entirely  new wire and drove an 8 foot stake into the ground to attach it too.  Maybe I should go cut that connection to make sure that the neutral cannot ever ground?  Geez, what people do on the internet to prove a friggin point....

[Monkeh]

If wired correctly the neutral side can act as Earth ground.

Ah.  Now I get it.  Trolling.  I was there when the electrician installed my new panel.  I can assure you my neutral is correctly installed and is tied to ground.  If you want to ignore the totality of a posting please just ignore it all.

And when you have an open neutral conductor, everything on the ungrounded side suddenly becomes hot. When you have an open ground, in the absence of any other fault, neither side is dangerous. This is the difference between a ground conductor and a grounded live conductor.

So no, it cannot act as a ground conductor because that is not wired correctly.

[hermit]

So no, it cannot act as a ground conductor because that is not wired correctly.

So in my example of it sitting in a flooded basement you are saying the neutral cannot be acting as a ground? 

[Monkeh]

So no, it cannot act as a ground conductor because that is not wired correctly.

So in my example of it sitting in a flooded basement you are saying the neutral cannot be acting as a ground?

Not particularly more than the ground itself. I don't see why you're bringing flooding into a wiring discussion - unless you're really enjoying arguing.

[RGB255_0_0]

I simply stated what is normally considered 'code'.  It has nothing to do with repair and everything to do with what can happen while it is sitting there doing nothing.  Having live current in an an otherwise idle device can do many things and probably most of them are bad.  That is why you switch the hot side.  If wired correctly the neutral side can act as Earth ground.  Which side would you switch?

If, as you say, your job is to know what the code is and you say that "neutral can act as earth ground" you are terrible at your job.  There is nothing in modern US code that says you can ever treat neutral as ground or safe.

Yes, it is normal and allowed to only switch the live wire on polarized equipment.  But double insulated equipment can and does switch both side (if it has a switch at all).  That does not mean that "neutral side can act as ground" which that is a dangerous, irresponsible, and incorrect thing to say.

Again, someone that wants to pull a few words out of context to prove their point.  If I go into my basement and find my circular saw half submerged in water from overnight flooding you are telling me the neutral CANNOT be acting as ground because that would be a "dangerous, irresponsible" thing for it to be doing?   

I think you believe current goes to ground and not neutral. In fact I'm incredibly unsure what you are thinking here.

[hermit]

So no, it cannot act as a ground conductor because that is not wired correctly.

So in my example of it sitting in a flooded basement you are saying the neutral cannot be acting as a ground?

Not particularly more than the ground itself. I don't see why you're bringing flooding into a wiring discussion - unless you're really enjoying arguing.

Strangely enough, your example is the reason not to switch neutral.  The whole idea behind it is added safety.  I never said it should be used as ground.    A properly installed and functioning neutral will generally be at ground potential so you wouldn't switch it anymore than you would any other ground.  I don't see what is so hard about that concept.  Adding the third wire ground to the existing 2 wire system was to account for the possibility of an open neutral.  I've seen that happen only once in 35 years.

But hey, this is an internet forum and fact is based on votes so I'll concede that I'm out voted and leave it at that.   Last post so pile it on and I won't dissent.

[KL27x]

Wiring a wall outlet is one thing. Manufacturing a powercord is another.  I dont see any reason to make a power cord in both straight and crossover. But apparently in europe this makes the cord safer.

[Zero999]

Design rules for appliances are always going to be slightly schizophrenic. They call for both active and return ( or live and neutral) conductors to have equal insulation on them, and that they should both be treated as being live conductors. Then the same regulations say that you should not fuse the neutral, and that there should not be a switch in the neutral side ( double pole switches that are designed to safely switch both conductors are allowed though) in this. Non polarised mains calls for fusing of both active conductors, and for for a switch that is either single pole or double throw. Hard to reconcile them both in a product made for a world market, unless you have 2 versions.

You're mixing up appliances and installations. There is no disconnect in the codes.

For appliances, it makes perfect sense to treat live and neutral the same, as in some areas of the world the plug can be rotated 180 deg without problem, and also, you never know which dork changed the plug at some point.

For installations, it's a different story, as they should be done by professionals, and switching and fusing only the live makes sense to avoid a ton of copper in the house.

I don't think he is confusing appliances and installations.

If the mains plug, is non-polarised then it makes sense to assume that either active conductor is phase.

If there's a polarised mains plug, then it's perfectly reasonable to assume that live and neutral are correctly wired up and the fuse and switch should always be on the phase side. When designing an appliance one must assume the installation is wired correctly and one can't be held liable for a shock/fire due to a faulty installation, i.e. reversed phase and earth conductor. I doubt anyone designing something with a 3 phase + neutral plug, would presume phase and neutral are interchangeable and consider switching two of the phases and the neutral.

In the case of an IEC connector, it's difficult because it depends on where in the world the appliance is designed to be used. You may argue that one should presume that live and neutral should be interchangeable, even if it's designed for use in a location with polarised mains connectors, in case someone takes it to a place with non-polarised connectors, but that may cause it to break some regulations such as fusing the neutral and if you take this stance, then what if the appliance is only rated to 120VAC and taking it to Europe would destroy it?

[KL27x]

Device the "wrong" cord came with actually states that is runs at 110 or 240. The IEC plug has "10A 240V" molded into it.

I was curious if there was a country with a north American style plug on it but the code that stipulates the IEC cable must be wired opposite from how we would choose to make the cable in the US. Or if this is just the manufacturer of said cable "helping us backward Americans be safer."

Me, I sometimes have a device opened up and plugged in. Trying to make/build/fix things. All in all, I rather my fuse be on the live wire, cuz the "double insulation" isn't there when I have the case open. Even then it's probably not a big deal. But I still don't see benefit of making these cables random.

(Curiously, I also see a lot of people complaining about fuse being on wrong line where it comes to one dude's 858D or other Chinese device. Me, I think messing up a simple power cord, which is probably a huge volume highly batched/automated/assembly line affair, is a bigger show of complete and utter laziness.)

[Benta]

Wiring a wall outlet is one thing. Manufacturing a powercord is another.  I dont see any reason to make a power cord in both straight and crossover. But apparently in europe this makes the cord safer.

No. There's no doubt that some of your power cords are wired incorrectly; for both the IEC connector as well as the wall connector that can only be plugged in one direction, there are codes.

But the most common Euro plug, which is the CEE 7/4, can be plugged in both directions. So it makes sense to design appliances without preferences as to what is live or neutral. And this increases safety.

[Benta]

I don't think he is confusing appliances and installations.

If the mains plug, is non-polarised then it makes sense to assume that either active conductor is phase.

If there's a polarised mains plug, then it's perfectly reasonable to assume that live and neutral are correctly wired up and the fuse and switch should always be on the phase side.

Unfortunately, this is a only in a dream world.

In the real world, a UK consumer* would buy a 230 V appliance from Amazon (or another online dealer) and get it delivered with a Schuko (CEE 7/4) cable, because that's how appliances are delivered these days (don't tell me it's illegal in the UK, because that's moot).
He will then go to his local electric shop and buy one of those nice cigar-box sized, 3-prong, UK-type plugs, cut off the Schuko and do the wiring of the plug himself.
Few people will have any idea of polarity, but there's always a little cardboard sign saying green/yellow must go to earth, making certain they don't kill themselves.

That's the reality. And that's why talking about live and neutral in an appliance is unhelpful. It's safer to treat them both as live.

* just an example, it applies to any 230 V country using polarized plugs, France/Belgium excepted (Schuko fits in their receptacles).

[Zero999]

I don't think he is confusing appliances and installations.

If the mains plug, is non-polarised then it makes sense to assume that either active conductor is phase.

If there's a polarised mains plug, then it's perfectly reasonable to assume that live and neutral are correctly wired up and the fuse and switch should always be on the phase side.

Unfortunately, this is a only in dream world.

In the real world, a UK consumer would buy a 230 V appliance from Amazon (or another online dealer) and get it delivered with a Schuko (CEE 7/4) cable, because that's how appliances are delivered these days (don't tell me it's illegal in the UK, because that's moot).
He will then go to his local electric shop and buy one of those nice cigar-box sized, 3-prong, UK-type plugs, cut off the Schuko and do the wiring of the plug himself.
Few people will have any idea of polarity, but there's always a little cardboard sign saying green/yellow must go to earth, making certain they don't kill themselves.

That's the reality.

The cardboard sign also shows which terminals the blue and brown should go to.

And in the case of shit from Amazon/ebay, the polarity of the live and neutral should be the least of your worries. The insulation is often crappy plastic with poor abrasion resistance and conductors copper plated aluminium and too thin for the current rating. The correct course of action is to discard the cable and buy the correct cable.

[Benta]

First, sorry, I was improving my post as you posted.

Second, I'm not talking about cr*p from Amazon, I'm talking brand products. Siemens, Bosch, Miele...

[Monkeh]

First, sorry, I was improving my post as you posted.

Second, I'm not talking about cr*p from Amazon, I'm talking brand products. Siemens, Bosch, Miele...).

That's Amazon's sourcing to get lower prices and isn't that common. How do I know? .. I live here and buy things.

[grumpydoc]

If the mains plug, is non-polarised then it makes sense to assume that either active conductor is phase.

If there's a polarised mains plug, then it's perfectly reasonable to assume that live and neutral are correctly wired up and the fuse and switch should always be on the phase side. When designing an appliance one must assume the installation is wired correctly and one can't be held liable for a shock/fire due to a faulty installation, i.e. reversed phase and earth conductor. I doubt anyone designing something with a 3 phase + neutral plug, would presume phase and neutral are interchangeable and consider switching two of the phases and the neutral.

It would seem that way but let me offer you a counter example.

If you are in France and plug in a piece of equipment which uses a Schuko to IEC lead you will almost certainly end up with live and neutral swapped in the equipment, despite the polarised plug.

The reason is that all of the Schuko to IEC leads that I have ever encountered (I suspect even those bought in France¹) are wired to the German pattern which puts the live on the left of the socket and the French put it on the right (as viewed looking into the socket as installed).

In fact the French "normes" only require the live on the right if the earth pin is at the top of the socket - if the socket has been inverted there is no convention.

Also - and, OK, I don't think this is entirely a fair criticism - if you use one of the Schuko to UK adapters in France you will find the British plug goes in upside down and live and neutral will be swapped - putting the fuse on the neutral side is not all that great for safety.

[1] I'm not sure whether any of the many Schuko  to IEC leads that I possess were bought in France, I suspect that they were all bought in the UK or that I acquired them in equipment where they were an "extra" because the box contained both a European and a UK lead. BUT all the ones that I have seen on sale in France look to be the usual Chinese imports and I doubt they do a French specific version but just ship the CEE 7/7 hybrid plug.

In the real world, a UK consumer* would buy a 230 V appliance from Amazon (or another online dealer) and get it delivered with a Schuko (CEE 7/4) cable, because that's how appliances are delivered these days (don't tell me it's illegal in the UK, because that's moot).
He will then go to his local electric shop and buy one of those nice cigar-box sized, 3-prong, UK-type plugs, cut off the Schuko and do the wiring of the plug himself.

Splitting hairs it will be delivered with a hybrid CEE 7/7 plug.

Also, unless bought via one of the European sites (amazon.fr, Amazon.de etc) it should be delivered with a IEC to BS1363 lead - in fact a lot of things that I have bought simply have both as noted above.

If not s/he probably will just go and buy a pre-made lead because most people are too lazy and too deskilled to wire a plug and the chances are a prefabricated lead costs less than a plug anyway.

[Benta]

If not s/he probably will just go and buy a pre-made lead because most people are too lazy and too deskilled to wire a plug and the chances are a prefabricated lead costs less than a plug.

Unless it's a fixed lead.

[Zero999]

If not s/he probably will just go and buy a pre-made lead because most people are too lazy and too deskilled to wire a plug and the chances are a prefabricated lead costs less than a plug.

Unless it's a fixed lead.

If it's a fixed lead, then it wouldn't be an IEC lead.

If the mains plug, is non-polarised then it makes sense to assume that either active conductor is phase.

If there's a polarised mains plug, then it's perfectly reasonable to assume that live and neutral are correctly wired up and the fuse and switch should always be on the phase side. When designing an appliance one must assume the installation is wired correctly and one can't be held liable for a shock/fire due to a faulty installation, i.e. reversed phase and earth conductor. I doubt anyone designing something with a 3 phase + neutral plug, would presume phase and neutral are interchangeable and consider switching two of the phases and the neutral.

It would seem that way but let me offer you a counter example.

If you are in France and plug in a piece of equipment which uses a Schuko to IEC lead you will almost certainly end up with live and neutral swapped in the equipment, despite the polarised plug.

The reason is that all of the Schuko to IEC leads that I have ever encountered (I suspect even those bought in France¹) are wired to the German pattern which puts the live on the left of the socket and the French put it on the right (as viewed looking into the socket as installed).

In fact the French "normes" only require the live on the right if the earth pin is at the top of the socket - if the socket has been inverted there is no convention.

Also - and, OK, I don't think this is entirely a fair criticism - if you use one of the Schuko to UK adapters in France you will find the British plug goes in upside down and live and neutral will be swapped - putting the fuse on the neutral side is not all that great for safety.

[1] I'm not sure whether any of the many Schuko  to IEC leads that I possess were bought in France, I suspect that they were all bought in the UK or that I acquired them in equipment where they were an "extra" because the box contained both a European and a UK lead. BUT all the ones that I have seen on sale in France look to be the usual Chinese imports and I doubt they do a French specific version but just ship the CEE 7/7 hybrid plug.

If something is designed to be safe and work properly in one location, one shouldn't expect it to do so elsewhere. Fine for appliances designed to work across Europe, then I concede that it's good practise to design for non-polarised, single phase mains, otherwise it's silly. For example, I use US appliances here in the UK, via a transformer. The line frequency is 50Hz, rather than 60Hz, which isn't good for the transformers. I accept that there's a risk of overheating and I'm probably voiding any warranties by operating the equipment outside its specification.

[Benta]

'nuff said. Good night 

[grumpydoc]

If something is designed to be safe and work properly in one location, one shouldn't expect it to do so elsewhere. Fine for appliances designed to work across Europe, then I concede that it's good practise to design for non-polarised, single phase mains, otherwise it's silly. For example, I use US appliances here in the UK, via a transformer. The line frequency is 50Hz, rather than 60Hz, which isn't good for the transformers. I accept that there's a risk of overheating and I'm probably voiding any warranties by operating the equipment outside its specification.

I did say that catering for the Schuck to BS1363 adapters was probably a bit much to ask manufacturers.

But the fact remains that despite polarised plugs there are still enough differences across Europe that you can't rely on which side is live when selling into that market - once you have designed around that for Europe there isn't any point in providing a variant for markets where you can guarantee which side is live (assuming a correct installation and correctly wired plug).

[tronde]

I found some interesting reading from Schneider Electric about earth systems.

https://www.eevblog.com/forum/beginners/electronics-primers-course-material-and-books/msg1273697/#msg1273697