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Posted By: pauluk Discussion of Legrand Wiring Diagrams - 10/27/02 09:04 PM
Thread for discussion of the Legrand International Wiring Diagrams posted here.



[This message has been edited by pauluk (edited 10-27-2002).]
Posted By: C-H Re: Discussion of Legrand Wiring Diagrams - 10/27/02 09:09 PM
Wow, now my head is spinning... I fail to see any major differences between the German and French wiring. Something wrong with me?

(Moderator: Thanks! But now you have to update the link above... Perhaps you should lock the other thread?)

[This message has been edited by C-H (edited 10-27-2002).]
Posted By: sparky Re: Discussion of Legrand Wiring Diagrams - 10/27/02 09:29 PM
wha??

something else of 'international' status besides the NEC????
[Linked Image]
Posted By: pauluk Re: Discussion of Legrand Wiring Diagrams - 10/27/02 09:31 PM
A few observations of my own:

AMERICAN SYSTEM
The first thing that struck me is all those EGCs drawn in green/yellow. OK, so an EGC is allowed under the NEC to have a yellow stripe now, but don't you normally reserve those for isolated grounds? The notes elsewhere do state "green or bare" which is fair comment, but I think the colors on the drawing are a little misleading for a "typical" installation.

While on the colors, look at the second small appliance branch. Again, we know that red could be used as hot, but is this typical? (Certainly not if Romex is used.) Anyone in the States feel that if they wanted to show some alternate use in a typical home it would have been better to add a multiwire circuit?

Next, look at the listed cable sizes below the drawing:- #14 for a 20A small appliance cct???

Take a look at the diagrams in the notes for NEMA 10-30 and 10-50 receptacles too. They've got them the wrong way round! (Correct on the main drawing though.)

Seems I'd be nit-picking if I added that it isn't really a 2-phase service sd they state, but technically only single-phase.

FRENCH SYSTEM
They say "usually single-phase." That certainly doesn't agree with my findings. I'd say that most homes in France have a 3-phase service and 1-ph is the exception. I've seen mostly older places rather than new, so does anyone know if higher rated
single-phase services are becoming more common nowadays for new homes?

I can't figure out the part about having to break both phase and neutral simultaneously, then stating that rewireable fuses are no longer allowed but HRC fuses can be used. How can an HRC satisfy the "both poles" requirement? [Linked Image]

BRITISH SYSTEM
One bit that looks a little suspect here is the lampholder shown wired directly into the ceiling pull-switch. They've shown it with brown/blue (i.e. flexible cord) colors, which suggests that the lamp pendant is connected directly into the switch. Is this supposed to be a combined pendant and
pull switch?




[This message has been edited by pauluk (edited 10-27-2002).]
Posted By: C-H Re: Discussion of Legrand Wiring Diagrams - 10/27/02 09:38 PM
Quote

FRENCH SYSTEM

I can't figure out the part about having to break both phase and neutral simultaneously, then stating that rewireable fuses are no longer allowed but HRC fuses can be used. How can an HRC satisfy the "both poles" requirement?

May I hazard a guess? Same way as the requirement for simultaneous break of all three phase conductors in Sweden: Three individual fuses side by side are considered one fuse "group" and numbered as one single fuse. (In fact, group ("grupp" in Swedish) is the word used when marking cables, sockets etc.)
Posted By: pauluk Re: Discussion of Legrand Wiring Diagrams - 10/27/02 09:42 PM
C-H,
I was locking the first thread as you put in your message and the only way out was to delete the whole thread and repost it.

I assume you can see all the diagrams? Can't seem to get them all back to my system at the moment, but I've double checked all the links.
Posted By: pauluk Re: Discussion of Legrand Wiring Diagrams - 10/27/02 09:47 PM
Sparky,
International as in examining various national systems, not international as in one system for all places.

C-H,
I think I see what you mean about a block, or group, of fuses. They would certainly break all poles simultaneously when pulled out by hand, but I was thinking along the lines of all poles having to open simultaneously in the event of a fault. I can't see how that can be achieved except with a circuit breaker.

As for the differences between the French and German systems, I don't think there are that many. France seems to prefer keeping lights on separate circuits to receptacles instead of mixing them together, and the notes specify that they also limit the number of outlets to eight on each circuit.
Posted By: Belgian Re: Discussion of Legrand Wiring Diagrams - 10/27/02 09:53 PM
>FRENCH SYSTEM
They say "usually single-phase." That certainly doesn't agree with my findings.
I'd say that most homes in France have a 3-phase service and 1-ph is the exception.
I've seen mostly older places rather than new, so does anyone know if higher rated
single-phase services are becoming more common nowadays for new homes?

I can try and answer for the French, since our system is nearly a copy of the French. When they say usually single phase, they're refering to new installations. Since the highest rate main Breakers is 63A, if you would need more , then you would have to make a demand for a 3 phase system.

>I can't figure out the part about having to break both phase and neutral simultaneously.

Read my reply in the thread plans, schemas...

>then stating that rewireable fuses are no longer allowed but HRC fuses can be used. How can an HRC satisfy the "both poles" requirement?

Why can't HRC satisfy the both pole requirement?
Posted By: C-H Re: Discussion of Legrand Wiring Diagrams - 10/27/02 09:57 PM
Yes, I can see all thee diagrams. No problems. Sorry for the inconvenience!

I think Sparky was joking about the NEC:s attempt to become THE international code. (They have made attempts to show that the NEC is superior to that of the International Electrical Commission. Now they apparently print International Electrical Code on the NEC cover...)

It can't be very hard writing a common European code, can it? I'm serious!

[This message has been edited by C-H (edited 10-27-2002).]
Posted By: Belgian Re: Discussion of Legrand Wiring Diagrams - 10/27/02 09:59 PM
Another difference is to do with the way they calculate the cable width to be used with each circuit.
Another difference between German and French are the plugs that are used. The reason that we adopted the French plugs instead of German is because the earth makes a contact before all other poles since it's pin is longer, whereas it's not the case with German plugs.

[This message has been edited by Belgian (edited 10-27-2002).]
Posted By: C-H Re: Discussion of Legrand Wiring Diagrams - 10/27/02 10:15 PM
Quote

Another difference between German and French are the plugs that are used. The reason that we adopted the French plugs instead of German is because the earth makes a contact before all other poles since it's pin is longer, whereas it's not the case with German plugs.

No, you adopted the French design because it was French... [Linked Image] Although the Schuko is a poor design with obvious drawbacks, the earth does in fact make contact first.

But, indeed, I would rather have had the French sockets here.
Posted By: Belgian Re: Discussion of Legrand Wiring Diagrams - 10/27/02 10:21 PM
How does the earth make contact first on a schuko plug?

According to what I understand from this document, the Germans also use TT system contrary to what you told me in a previous thread, CH, that they use, too TN system. So we are not the odd ones [Linked Image]


[This message has been edited by Belgian (edited 10-27-2002).]
Posted By: CTwireman Re: Discussion of Legrand Wiring Diagrams - 10/28/02 01:01 AM
Good observations, Paul. I see you have learned some of the nuances of American wiring quite well. [Linked Image]

Green/yellow is not representative of a typical installation. Isolated ground circuits are almost non-existent in a home. In a residence, bare would be more accurate, for obvious reasons.

#14 is never used on NEC-mandated appliance circuits.

Yes, I second your statement about multiwires. They are extremely common here and probably should be added to the diagram.

As you mentioned, red could not be feeding that water heater if Romex was used.

That diagram is also outdated, since no ground wire is shown going to the range or dryer. The practice of using the neutral for the ground on ranges and dryers is now forbidden.

BTW, I would hate to use one of your 16mm or 25m boxes. The lack of depth would drive me nuts. As it is, I dislike our 18 cubic inch boxes which are 2.5" (62mm) deep! I always use 20 or 22 cubic inch boxes, which are much deeper.

[This message has been edited by CTwireman (edited 10-27-2002).]
This is about the best summary of all these systems I've ever seen. Thanks for posting it!
Our boxes are 60mm in diameter and 50 mm deep (according to some internet source, I've got to check that some time). With that, you're already in trouble with some wall types. Many early 1900s housers here have 50 mm solid gypsum compound walls, with just about 3mm plaster on each side. I've seen elctricians saw off the back of their boxes in order to get them into these walls without ripping a hole all through the wall. Personally I wouldn't want to make too much connections inside them, but there's enough room for some block connectors.
Posted By: sparky Re: Discussion of Legrand Wiring Diagrams - 10/28/02 11:54 AM
Quote
I think Sparky was joking about the NEC:s attempt to become THE international code. (They have made attempts to show that the NEC is superior to that of the International Electrical Commission. Now they apparently print International Electrical Code on the NEC cover...)

yes of course.... taken here in a rather egotistic light if i may.... predictated on international trade, blah, blah, blah...note we've the metric system much more prononced, not that any of us really can use it effectively
[Linked Image]
Posted By: C-H Re: Discussion of Legrand Wiring Diagrams - 10/28/02 02:31 PM
>How does the earth make contact first on a schuko plug?

I tested this with a couple of sockets yesterday. The earth "rails" (can someone please tell me what I should call these?) on the side of the socket comes in contact with the metal strips on the plug about 2 mm before the live and neutral pins make contact.

Quote

According to what I understand from this document, the Germans also use TT system contrary to what you told me in a previous thread, CH, that they use, too TN system. So we are not the odd ones

You're right. The diagram really shows a TT system. And, yes, as far as I know both the TT and TN are in fact used in Germany. Legrand (French company) probably felt it more comfortable to draw a TT system.
Posted By: Belgian Re: Discussion of Legrand Wiring Diagrams - 10/28/02 04:21 PM
>BTW, I would hate to use one of your 16mm or 25m boxes. The lack of depth would drive me nuts.

Same here!
We have the choice to use whichever depth we want ranging from 40 to 60mm diep. We also have special boxes for walls which are hollow eg Gyproc.
Posted By: SvenNYC Re: Discussion of Legrand Wiring Diagrams - 10/28/02 05:36 PM
What sort of strikes me as weird is the statement in the British section that says "BS 546 sockets are no longer used in the UK."

I thought these were regularly used in the theatre industry and also for some residential lighting circuits-switched sockets (for a table or floor lamp controlled by a wall switch). At least that's what I've seen on the UseNet uk.diy newsgroup.
Posted By: C-H Re: Discussion of Legrand Wiring Diagrams - 10/28/02 05:57 PM
Quote

What sort of strikes me as weird is the statement in the British section that says "BS 546 sockets are no longer used in the UK."
I thought these were regularly used in the theatre industry and also for some residential lighting circuits-switched sockets (for a table or floor lamp controlled by a wall switch).

The purpose is to clear up the misunderstanding that BS546 are still used as general purpose sockets. Most travel sites and adaptor vendors tell you that BS 546 is just as common as the new 13A plug, and that you therefore have to buy both adaptors when going to the UK. Nobody in his/her right mind would plug in their laptop or hair dryer in a stage lighting socket. In short - these and other special sockets are used to prevent people from plugging in anything else than the intended equipment.

The same problem exist for US adaptors. Some list several of the NEMA designs, whereas you in reality will always have a 120V 15A socket to plug into. You are not supposed to plug your laptop into the tumbler socket...
Posted By: David UK Re: Discussion of Legrand Wiring Diagrams - 10/28/02 10:41 PM
Thanks C-H
I couldn't have put it better myself.
BS 546 sockets are only for special purpose use nowadays, you do not find them in general residential use.
True, 2A & 5A types can be used for lamp sockets switched from the door, but very few British homes have this arrangement.

I would point out that this guide is around 10 years old, so inevitably it will now be out of date or inaccurate.
I'm pleased it's got everyone talking!
Posted By: pauluk Re: Discussion of Legrand Wiring Diagrams - 10/29/02 10:37 AM
Glad to see this has provoked a lively discussion! [Linked Image]

Sparky,
Sorry if I missed the irony first time -- I must have been tired that night. I too noticed that the '02 NEC now has everything in English & metric units. When the British IEE decided to change over with the 1970 edition they just dropped English measurements completely in favor of metric. Not a good decision in my opinion.

CT,
I hadn't thought about the colors where Romex is used on a 240V (no neutral) circuit like the water heater, but I take the point. I was looking at the small appliance branch (120V only, not multiwire) shown in red and white.

The point several of you have made about the depth (or lack thereof) of British boxes is one of my major grumbles about our fittings. Wiring space is very cramped in many cases, especially at something like a double receptacle where a spur cable has been added. I like to use deeper boxes wherever I can, but it's not always easy when dealing with the masonry walls which are so common here.


Sven,
Quote
I thought these were regularly used in the theatre industry and also for some residential lighting circuits-switched sockets
The 2A types used to be found quite regularly for switched lighting outlets in some homes, but as David has pointed out, the practice is almost extinct these days.

You're right about BS546 plugs in theatre applications though. Aside from any desire to make the plugs non-interchangeable, there's a much more practical reason for using them.

Regular 13A plugs all contain a fuse. It's not uncommon for a suspended spotlight to be fed through half a dozen or more different extensions and connectors from the control booth. If a lamp burns out, it's enough trouble to get the ladders out and climb up to change the bulb. If the bulb shorts out (or some other fault blows a fuse) you don't want to have to trace all the extensions back to find which of the many fuses opened the circuit. (Yes, I've been involved with the lighting & sound for amateur dramatics!)




[This message has been edited by pauluk (edited 10-29-2002).]
Posted By: pauluk Re: Discussion of Legrand Wiring Diagrams - 10/29/02 10:49 AM
Quote
It can't be very hard writing a common European code, can it? I'm serious!

C-H,
I think there's a problem getting the various national organizations to agree over certain points. In Europe, as in America, you happily accept a GFI/RCD-protected outlet in a bathroom, for example. (Related question: The American NEC actually requires such an outlet; do the various European codes require one?) The British IEE seems unwilling to budge from the viewpoint that the only receptacle in a bathroom should be a low-power shaver outlet fed via an isolating transformer.

The Schuko plug, like it or not, is the most commonly used connector in Europe now and it seems likely that it would be chosen as the standard plug for a Europe-wide code. Again the IEE here (and maybe the equivalent bodies in some other countries?) is firmly against the use of an unpolarized plug.

Belgian,
The French-style plug is polarized, of course, but in my experience there doesn't seem to be much consensus as to which way round line & neutral are connected at an outlet. Is there an official French/Belgian standard on this, or are the positions undefined?
Posted By: Belgian Re: Discussion of Legrand Wiring Diagrams - 10/29/02 02:35 PM
Quote
Belgian,
The French-style plug is polarized, of course, but in my experience there doesn't seem to be much consensus as to which way round line & neutral are connected at an outlet. Is there an official French/Belgian standard on this, or are the positions undefined?

No, there is no standard, but remember our Neutral is also protected by the breaker.

[This message has been edited by Belgian (edited 10-29-2002).]
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