Hi everyone:

I'm an engineer in England and came across your board quite by accident a couple of weeks ago.

I have spent time in the States, and although I don't know the details of the NEC, I am familiar with your general wiring practices, etc.

It's really interesting to read your messages and compare the topics and problems being discussed with the sort of problems we run up against here in the U.K.

If anyone is curious about any aspect of how things are done over here, I'd be happy to oblige.

Hi Paul;
tell us a little about wiring methods in the UK please, maybe some differences that you've seen would be interesting.

Paul,

Welcome!
Yes, by all means share with us. I've heard that circuits are connected in a "Ring" How does that work and what are the benefits or downsides in doing that?


Bill

My welcome as well!
I'm quite intrigued with the way things are wired in different places.
Don't you have some sort of fusing at the point of use?

Hi Sparky,

There are so many differences between U.K. and U.S. practice that they could easily fill a book. Here are a few to start you thinking!

You may well know this already, but our standard residential service is 2-wire at 240V, 50 Hz, so all our domestic appliances run on 240V, not a mix of 120 and 240. The neutral is grounded ("earthed" in British terminology) so the hot wire ("live") is a full 240V with respect to ground.

We have completely different types of plugs and sockets, and as you might expect, different standard mounting box sizes etc. Our color code is different, and as anyone who has visited the U.K. will have soon realized, our light switches are up for off, down for on.

There are far more fundamental differences in circuit arrangements. For example, in British homes it's usual for lights to be wired on separate circuits to sockets (receptacles), partly for historical reasons and partly because of the system used to distribute power to wall outlets.

As there are two questions here relating to the latter, I'll try to answer them in a separate post.

Fire away with your 200 follow-up questions.....

Hi Bill & Electure:

Your two posts are somewhat related, so I'll try to answer them together.

Yes, we do have ring circuits and fusing at point of use. The ring arrangement was introduced in the late 1940s. Prior to that we had several different types of plug in use, rated at 2, 5 and 15 amps, all with round pins.

The ring arrangement saw the introduction of a new type of plug which was intended to be a universal connector for portable appliances. A ring circuit is wired from a 30A fuse or breaker at the panel to each socket in turn and back to the panel to complete the ring. All three conductors (live, neutral, earth) are wired in a ring.
30 amps at 240V is a lot of power, so the house fuse is there just to protect the ring wiring. The plug has three rectangular pins and is rated at 13A max. (chosen to allow for a load of up to 3kW). Every 13-amp plug (known officially by Briish Standards as a BS1363 plug) is fitted with a small cartridge fuse, which is available in several different ratings up to the 13A maximum.

Advantages of the ring:

A 30A ring can provide up to 7200W and can serve a large area (up to 1000 sq. ft. for each ring is the accepted limit). Each portable appliance has its own fuse in the plug. Smaller, easier-to-work cable can be used than would otherwise be needed for a 30A branch.

Disadvantages:

Overcurrent protection for the cable relies on the integrity of the ring; a broken live or neutral will still leave all outlets energized, but a dangerous overload could occur. Mr. Joe Public often has no idea what size fuse should be in each plug and runs everything with a 13A fuse "Because it's a 13-amp plug." Adding extra outlets entails more work to maintain the ring. DIY extensions often result in a broken ring or a dangerous spur (spurs are O.K. under certain conditions).

These are some of the main pros and cons put forward frequently. Personally, I'm not that keen on rings and prefer other arrangements.

Over to you...

To say it in plain "English", with the ring, there are two ("parallel") electrical paths to each outlet; therefore, the conductor needs only to be half the ampacity.


Putting light switches in upside down goes along with driving on the wrong side of the road.

But on a serious note, how are the pronga on your receptacles oriented? Do you put them with the earthed conductors up?

Hi,

Yes, the smaller cable which can be used because of the parallel paths is probably the the most widely claimed advantage of the ring.

We only use them for feeding sockets, however, and everything else is wired in the more conventional way.

A typical small older house might have a 30A ring for wall outlets, a 30A branch for a cooker (range), a 15A branch for a water heater (almost always 3kW here) and a 5A branch for lighting.

Most houses these days, and larger or higher budget ones in the past use two 5A lighting circuits and two 30A rings.

As for the switches, I actually prefer the American up for on, down for off! It just seems more natural to me. (Don't mind which side of the road I drive; I'm happy on the left or the right!)

All of our sockets, both the older round-pin types and the newer rectangular-pin ones are arranged with the earth/ground at the top. Neutral is then below it to the left and live/hot to the right.

I've seen U.S. receptacles mounted both ways up. Is there an accepted standard, or is it just a matter of the electrician's preference?

I've seen U.S. receptacles mounted both ways up. Is there an accepted standard, or is it just a matter of the electrician's preference

Paul;
It's actually highly debated, that's why we are curious. So is it a 'code' to install them in the manner you descibe ??

>Neutral is then below it to the left and live/hot to the right.
Those positions are swapped compared the 120 V receptacles.

>Is there an accepted standard, or is it just a matter of the electrician's preference?

It might be someone's preference. Many accessories are laid out assuming that the ground prong will be down. But I personally prefer them up.

Paul, I was doing start up on a power plant with an engineer from the UK recently. When making up a small motor he commented on the wire nuts I was using. He said electricians back home would only us them for temporary situations and said he was supprised to see we use them everywhere. Have twist on wire nuts not gained general acceptance over there from what you have seen?
Nick

No, there's nothing in the I.E.E. Regs. to say earth should be at the top.

However, all of our 3-pin plugs are the type that I think you would refer to as right-angle caps, i.e. the cord emerges downward rather than outward, so any other orientaion seems awkward.

Another point is that the majority of our outlets fitted in homes have built-in switches mounted on the upper portion of the wall plate, so fitting outlets the "wrong" way would put the switches below the plugs and have them operating upside down (from the British point of view, that is!).

Very occasionally you might see sockets mounted sideways in a tight spot, and I have seen a couple upside down, but it's very rare.

By the way, our "twin" sockets (i.e. a duplex) are side by side instead of one above the other.

What proportion of U.S. receptacles would you say are fitted each way?

Nick:

Wire nuts are rare here. In fact many electrical suppliers don't carry them and requests for them will quite likely be met with a puzzled "What?"

I've seen them used for the internal splices in some light fittings (usually imported from the Far East), but that's about all.

As far as residential wiring is concerned, 99% is done in PVC-sheathed "twin & earth" (similar to Romex), and we have purpose built plastic junction boxes with brass screw terminals molded into the base.

Where an extra wire needs splicing behind an outlet or other accessory we use the "chocolate block" type screw connectors.

Do you know when wire nuts came into common use in the States?

Paul,

The majority of receptacles are with the grounding hole down. From my observations I would say maybe 95% of Residential receptacles are that way. Right-Angle plugs seem to be oriented that way.

Bill

It was way before my time. Maybe some of the "more experienced" (older) folks on this site could shed some light. Judging from existing work I have seen I would say the late 60's.
Nick

I think wirenuts came along about when I was a baby, in the early-mid '50s.
Paul,
I've never heard of a "chocolate block" connector. Could you describe one?
It's interesting that your boxes and receptacles are a unit, given the multitudes of component combinations we use here.

Hi guys,

I just had to jump in here. Really interesting reading about Britian's differences in wiring. Paul's description of his "box and receptacle in one" sounds a lot like the combination device/box used in the modular home industry here in the Midwest. They look like PVC remodel boxes with the flip up "wings" and an integral device molded into the box. Pain in the rear to repair, but they must be fast to install.

Dallas

Most of the fittings used for domestic work here are a combined switch/socket and faceplate. Single sockets come on a 1-gang plate abut 3.25 i. square, while a 2-gang is the same height but about 5.75 in. wide.

It's possible to buy 1, 2, or 3 switches in the 1-gang size, and up to 6 on the 2-gang.

The mounting boxes are separate: Most new work uses metal boxes which have knock-outs, but plastic boxes matching the accessories are available for surface mounting. Plasterboard boxes are comparatively new, and have twist-out lugs for wall mounting where there's no stud or noggin handy.

Modular fittings with separate accessories and cover plates are used as well, but they work out more expensive so tend to be used only in commercial applications.

I post some pics but I'm afraid I don't have a scanner.

If wire-nuts came into use sometime in the 1950s, then no prizes for guessing my next quetion. What was used before? Some other type of connector, or soldered and taped joints?

Electure:
The "chocolate block" connector. Imagine a small plated brass tube, about a half inch long. Wires are slid into the tube and two screws tapped through the wall at either end clamp the wires in place. The tube is enclosed by a plastic surround which has two round extensions to cover the heads of the screws. They are usually supplied in strips of 10 or 12 with th plastic molding linking hem together. You can cut off one, two, or as many as needed in one strip. Originally the plastic was dark brown (hence "chocolate block"), but these days most are a clear translucent plastic. The come in different sizes, like wire nuts.

Bill:
In Australia and New Zealand they use plugs which have 3 flat blades similar to those on U.S. plugs. Their outlets are oriented with the ground at the bottom.

Hi!
Have been following the discussion about the UK/US wiring methods (very interesting by the way). Since I’m Swedish, I have some trouble understanding everything that’s written. Especially technical names on different wiring material. So I have a question, what exactly is a wire-nut? In Sweden we have something called “Top-clamp” (directly translated from Swedish). It’s like a small plastic cone in witch you twist the wires together. Is that something similar to a wire-nut?

>I think wirenuts came along ... in the early-mid '50s.
Perhaps so. But they weren't in common use until long after that based on what Nick and I have seen.

>In Sweden we have something called “Top-clamp” ... a small plastic cone in which you twist the wires together. Is that something similar to a wire-nut?
That sounds exactly like it.

Our preferred ones have a copper "spring" (closely wrapped spiral) inside the cone that screws down tight on the wires.

kent,

Welcome!
You description sounds like our "Wirenuts"
Here is a picture of some common ones. They come in different sizes.



Bill

Kent,
A friend of mine's wife is from Sweden and they moved there about a year ago. He is working as an electrician in Sweden now. When he first started he got in trouble from his boss for double wrapping tie wire to tie things off. Apparently metal is a rare and expensive commodity in Sweden! Is this true? We use tie wire over here like it grows on trees!
Also, I understand you use alot of glue or silicon to mount wiring to wall panels.
Nick

pauluk and the rest of the gang. the chocolate blocks sound very similair to the terminals used in industrial applications here, except that we use them mounted in a metal strip that is screwed to the backplane of a panel. It is interesting to here of other countries methods , especially the UK since I can trace my ancestors to there.

Before wirenuts, and after solder and tape, at least in this area, crimp on barrels were used for conductor splicing. They were taped.
Their use was continued in residential wiring long after wirenuts were around. The wirenuts became popular early on in commercial and industrial applications because they could be removed and conductors could be added or taken off without having to cut anything.

Nick

It sounds like your friend’s boss is holding the company wallet pretty tight. At my firm we have no restriction on the use of tie wire, we use it a lot in industrial installations to fasten cables on what we call “cable ladders” (I don’t now if the last is a World Wide term). About the glue business, some people use melting glue to fasten the PVC pipes which is used for “hidden wiring”. I really don’t know how common it is. In the area I work we use ordinary nails. You US guys seem to use a lot of metal pipes when wiring, even on the outside of walls. Do you use pipes and “lose wires” instead of cables or have I completely misunderstood the photos I seen?

kent,

If you've got any interesting pictures of work over there I'm sure We'd be interested in seeing them. If you send them (with breif description) to Me I'll post them here.

The same goes for any of our other visitors reading this.


Bill
Bill@Electrical-Contractor.net

Hello Kent:

Compared to the other guys on here, you're practically a next-door neighbor to me in Sweden!

I'm sure everyone will forgive your not understanding all the terminology - I doubt anyone else here knows any Swedish whatsoever!

The "pipes" you refer to for running wires are known as "conduit." We use it here in England as well, but mostly on industrial work. It's almost never used on domestic wiring in the U.K. (even for the service entrance), but it's more common in the States because they have stricter codes which specify that it must be used in certain places.

I think the "cable ladder" you mentioned sounds like what we would call "cable tray."

Bill

What type of photos would you like to see? Pic's of installations, electric material used in Sweden, code violations? Tell me and maybe I can get some.

Hi Pauluk.

Yeah, Sweden / UK may have more things in common than Sweden / US . Much thanks to the EU I think. About the pipes. We uses “conduit’s” ( OPG-Pipes they are called here and can be built together by using pre-fabricated bends and seams) as well to protect wiring from mechanical damage, but like you said mostly in industrial work. I’ve seen some work here in Sweden from the 40’s or 50’s where conduits was used for running wires on the outside of walls.

In concealed residential wiring from the 40’s and 50’s maybe even some part of the 60’s they used something called “panzer pipes”. Junction boxes and boxes for light switches and sockets (I don’t think they are called boxes but I think you know what I mean) where also made of metal. One time I was searching for a electric fault in a house built in the late 50’s. My test instrument had probes which was not completely insulated. I had placed one probe on a live (240V) and was just about to remove it when it accidentally touched the box. BAM. The box was in some way, through the pipes, connected to ground. I don’t think the pipes or the box was grounded by intention it was more likely a coincidence.

Kent,

Anything that you care to send. Violation photos are especially of interest to us. But if there are standard wiring practices or materials that differ from our own, they are interesting too. What does your standard Electrical service look like for example? That might be different than ours.

Bill

Kent,

Yes, I think the EU is working toward standardizing just about everything in our part of the world. There are still some obstacles to electrical matters from our I.E.E., though.

As you will know, the "Schuko" plug that you use is about the most widely used in Europe, but our committees in the U.K. are reluctant to adopt it because it's non-polarized (i.e. there's no way to guarantee which way line and neutral are connected).

With regard to the grounded boxes and conduit you found, I would have thought this was standard practice in Sweden.
Our IEE Regulations here certainly specify that all metallic conduits and boxes must be grounded, and even though compliance with the Regs.is not compulsory for residential wiring, no decent electrician would ever leave boxes without a ground. (Just think what would happen if a live wire shorted to the inside of a conduit.)
Sweden has quite a reputation for safety matters, so I'm sure this wouldn't have been overlooked.

Incidentally, I know most distribution in Scandinavia is 3-phase 220/380V, but I know some areas have a 220V service fed from a transformer with a grounded center tap. Do you have any of these systems in Sweden?

Bill,

I have no idea what the standard electrical service entrance is like in Sweden, but our system in the U.K. is very different to yours.

Without the aid of photos it'll take some describing, so I'll post details in a new thread when I get a chance.

Pauluk (and the rest of you guys if your
interested)

You may be right about the boxes and pipes, but things which are meant to be grounded (both now and back in the days) usually has a screw-connection for the ground wire. These boxes has no such and the pipes have no visible grounding point either. The boxes used to have some kind of paper insulation but when it gets old it starts to fall apart.


Yes, we have a 3-phase 240/400V (they raised the voltage some years ago) direct ground system (the transformer centre point is connected to ground) for public distribution. The customer receives 3-phases and a joined neutral /ground (PEN). The power companies talks about start using a 5-wire system from their junction in the street and in to the houses, but I don’t think it is in use yet.

If I understand things correctly households in England has a single-phase service at 240V. So you run everything on 240. Stoves, boilers, washing machines, electrical heating and so on?

A little about the colour code. We use black as phase, blue as neutral and green/yellow as ground. Our fixed 3-wire cables uses the same colours. Add a brown for the 4-wire cables and a white for the 5. Plastic flexible 3-wire cords, brown, blue, green/yellow. Cables with larger dimensions (for let’s say 16amp and up) have all black wires marked with numbers (tiny and sometimes hard to read) 1-3 or 1-4 and a copper “shield” witch is used for ground. I think these types of cables in the future will become colour coded as well.

I saw the word “Romex” on the forum. What exactly is it and is it the most common cable for residential work?

I feel a small need to apologise for my crappy English but it’s a bit tricky for me you know.

Kent:

I've never heard of metal fixture boxes which are then insulated. We've certainly never used anything like that here.

We adopted the common European brown, blue, green/yellow colours in 1970, but only for flexible cords. Fixed wiring cables continued with our old system of red for phase, black for neutral, green for ground.
Green/yellow is now used for ground on fixed cables as well, but we still use red and black.

When flexibles are used for 3-phase now, all 3 phase conductors are brown, and we also use letters or numbers to identify them if phase rotation or identification is important.

Do I take it that black, brown, and white are your standard colours for 3 phase fixed wiring? Ours are red, yellow, and blue (since 1965).

Yes, houses in the U.K. normally get a single-phase 240V service, rated at 100A on almost all new houses, although a lot of older 60 and 80A services are still in use, and even a few 40A ones.

I think 3-phase for residential use is quite common across Continental Europe, isn't it? I know this is certainly the case in France, where I have seen some houses with a 3-phase supply of as little as 15A per phase.

"Twin & earth" is the cable used for 99% of residential wiring in England. It consists of an outer oval-shaped PVC sheath in grey or white, containing two PVC-insulated wires for line & neutral between which is a bare copper ground wire. We also have "triple & earth" which is used for 2-way light switching, etc.

"Romex" is the American equivalent, but with a different colour code. In case you didn't know, in America they use black for phase and white for neutral.

>2-way light switching
We call it three-way.

Romex is a brand name used to refer to non-metallic sheathed cable.

I was aware of that - Just another of those little differences in terminology, but I thought Kent in Sweden would probably be more likely to know it as 2-way.

I know you can get Romex in 2-way (black, white) and 3-way (black, white, red) with & without ground, but do they make it in any other versions?

Kent,

I was just thinking how good your English was! You have no reason at all for apology. It is better than many natives around here speak!


Bill

>... Romex ... do they make it in any other versions?

I believe that you can custom order just about any number of conductors and colors that you wish... the same goes for metal jacketed cables.

LOL !
the truth is, 1/2 of America can't understand the other 1/2's accent

In England one only has to drive 50 miles and the local accent can be completely different.

Those of us from the south of the country (which includes me, as I'm from London originally) have a hard time understanding a lot of the northerners. Run into somebody from Glasgow (Scotland) or Belfast (Northern Ireland) and there's no hope of understanding a word!

Kent:

There's no need to apologize for your English - it's much better than the English used by many people in Britain.

It seems to me that almost everybody in northern Europe (from the Netherlands north) seems to speak at least some English.

I think most of us who have English as our first language (U.K., U.S., Australia, etc.) are very lazy when it comes to foreign languages. I can speak just enough French to ask for things in shops or to understand directions when I'm in France, but I still feel very inadequate.

I sometimes wonder if english is going to stay our 1st language here

I take it you're referring to Spanish becoming more and more common.

When I was going through the very-laborious process of getting my green card and work permits I had to make regular calls to the INS, and all their computerized "help" systems offered the choice of English or Spanish.

yes Paul;
I do now regret having no interest in high school spanish. Having few actual 'ligustic' boarders in the US lends to being lazy, yet the exponential influx of spanish speakers may change that, as it already has had an impact on the school systems here.

We're lazy about foreign languages here as well. I suppose with English being an international business language (partly thanks to the U.S.A. of course) and with so many Europeans speaking English as a second language most of us just never have any real incentive to learn.

I recall hearing a news story when I was over there last about California trying to pass a bill to make English the state's official language. Apparently, although many states did pass such laws last century, this never happened in Cal. and the state actually hs no legal official language.

>I know you can get Romex in 2-way (black, white) and 3-way (black, white, red) with & without ground, but do they make it in any other versions?

I'll jump in here with a Canadian perspective. We call it loomex, based on the historical construction method of the cable which was cotton loom impregnated with bitumen to insulate each conductor, paper spiral wrap around each conductor, with an overall outer jacket of cotton loom impregnated with bitumen. No bonding conductor in the older cables, but since the 60's all loomex comes with a bare bonding conductor.

Present-day construction is thermoplastic or thermosetting insulation on each conductor with an overall PVC jacket.

Available in black/white, black/red/white, and black/red. White is what we call the 'identified' conductor, and is always used as the neutral. Black is hot, red is hot, and are fed either from a split 240/120V single-phase panel so that there is 240V potential between black-red, or from two phases of a 208/120V 3-phase panel so that there is 208V potential between black-red.

The black/red type of loomex is sometimes called Heatex because it is used for 208V or 240V feeds to baseboard heaters and water heaters. We used to be permitted to use black/white loomex to run 208/240V circuits, but it is mandatory now to use the black/red type of cable.

Regards,
Brian

We used to have similar cotton-based cables here, usually as a covering for a rubber insulation. Thermoplastic is the standard now, with butyl rubber for high-temp. work.

When you used to use black/white "loomex" for a 208 or 240V circuit, I assume that the CEC required the white to be tagged black or red at each end ??

You'll find some of my posts for U.K. color coding in this section.

>When you used to use black/white "loomex" for a 208 or 240V circuit, I assume that the CEC required the white to be tagged black or red at each end ??

Actually the CEC never did explicitly permit the white conductor to be marked a different colour. The electrical inspectors would just ignore the situation because cable with only red/black conductors weren't available.

Regards,
Brian

So do I assume that the CEC also didn't officially allow black/white loomex to be used as a switch drop, even if it was used in practice?

Over here, black is reserved for the neutral, but the regs. allow it to be used as a hot wire if it is suitably tagged at each end. For example, our standard 2-w plus gnd cable is red & black, so on a switch drop we normally use red as the feed and black, taped red, as the line to the light.