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#132714 - 08/20/01 12:33 PM U.K. Residential service entrance
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
I promised you guys a description of our typical domestic service entrance. Pity I'm not able to post some pics, but nevermind.....

Meters are usually located outside on all new homes now, but until quite recently standard practice was for all meters to be inside the property. Just thought I'd explain that first.

The meter and associated equipment is usually mounted on a wooden board about 18 inches square.

On older property in urban areas, the service was generally from an armored underground cable and the board mounted close to the entrance point on the ground floor, often in a cupboard. (Basements are much rarer here than in the U.S., but some old Victorian houses with a coal cellar had the service fitted down in the cellar.)

Most rural property was served with overhead lines. A bracket with two porcelain insulators is used to terinate the pair of supply lines (the neutral often being bare up to this point). From there, two cables with a double layer of PVC insulation run down and through the wall to the board, in this case normally mounted at high level on the ground floor.

The newest system, now used in all areas, has a PVC sheathed cable with center "live" wire and a concentric neutral. Even where overhead distribution is employed, these new feeders are run underground to the nearest pole.

The armored cable, concentric cable, or two single cables terminate at a service block containing the main fuse and a neutral link. (On overhead systems with separate line/neutral cables, these were often separate.) Most new services are 100A, but a lot of older 80, 60, and even some 40A services are still in use.

On installations using PME (see my other posts), this neutral link is also the point at which the main grounding lead is connected to the neutral.

From here, two double PVC insulated cables link to the meter, which has large screw terminals instead of being a plug-in type. Two more similar cables exit. Everything up to this point is the property of, is installed by, and is maintained by the utility co. The meter case, terminal cover, and main fuse are all sealed. Note that none of this wiring is in conduit or raceway.

On the simplest installations, the cables then continue to a "consumer unit" which contains a main switch and the individual fuses or breakers. In cases where an ELCB is fitted, this is wired between the meter and the consumer unit. On new installations needing a whole-house ELCB/GFCI, this is more usually fitted in the consumer unit where it takes the place of the main switch.

Where outside meters are used, a white plastic (ABS) box with a door is fitted on or set into an exterior wall to hold the board for the meter and service block/fuse. The remaining equipment is still fitted inside the building.

This is all for a basic service; many homes have dual-tariff meters and PoCo-owned timers etc. to provide low-rate night service.

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#132715 - 08/20/01 04:05 PM Re: U.K. Residential service entrance
sparky Offline
Member

Registered: 10/18/00
Posts: 5545
Meters are usually located outside on all new homes now, but until quite recently standard practice was for all meters to be inside the property.
LOL! it's just about the opposite for us here, at least on the east coast. Those meter readers don't want to knock on doors.

The newest system, now used in all areas, has a PVC sheathed cable with center "live" wire and a concentric neutral
So, each individual conductor has it's own nuetral?

On installations using PME (see my other posts), this neutral link is also the point at which the main grounding lead is connected to the neutral.
well that sounds like our setup...i am confused...is this the norm? Is there any nuetral isolation back to the X-former?

Everything up to this point is the property of, is installed by, and is maintained by the utility co.
sounds like here also, does the utility allow an electrician to yank the meter to change a panel there?

Paul;
please excuse all my quoting of you, I type slow

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#132716 - 08/21/01 12:00 PM Re: U.K. Residential service entrance
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
I think they've started going for outside meters here for the same reason. More houses are often empty a lot these days (two-income families etc.), more so than in the past, and it saves the meter reader a lot of time.

Some of the old service entrances really were in awkward places, and meter readers always carried a flashlight. When at the back of a cupboard, the meter and main panel often got hidden behind a ton of junk.

It made for some gags in films though: Husband returns early, ruffled guy crawls out from under bed or inside wardrobe and says "They really put those meters in some funny places!"


So, each individual conductor has it's own nuetral?


No. Remember that residential service here in only 2-wire, so there's only one "hot" line (at 240V to ground).

And for 3-ph. commercial service, the new cables have the 3 phase wires inside a single concentric neutral.


well that sounds like our setup...i am confused...is this the norm? Is there any

There is NO link between neutral & ground at the customer's premises, EXCEPT when the PME system is in use. I hope I've clarified this in my other msgs, but yell if you're still confused!

does the utility allow an electrician to yank the meter to change a panel there?

Most definitely not! If someone broke a seal to pull the main fuse in a genuine emergency (e.g. flames coming out of the meter/panel!) and then notified the Co. immediately, I'm pretty sure they'd accept it, but otherwise they get quite annoyed. Technically, it's a criminal offense for anyone but the PoCo. to break any of the seals.

I take it that you can do this, at least in your area?

please excuse all my quoting of you, I type slow

"Pas de probleme," as they say in France!

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#132717 - 08/21/01 05:19 PM Re: U.K. Residential service entrance
sparky Offline
Member

Registered: 10/18/00
Posts: 5545
There is NO link between neutral & ground at the customer's premises, EXCEPT when the PME system is in use. I hope I've clarified this in my other msgs, but yell if you're still confused!

Thanks, sorry for the fuss. The 'dual-usage' of a conductor as both N & G here in service entrance wire creates a lot of confusion per application of some of the finer NEC requirements. I have been made to understand that the ultimate 'fix' for much of this would be said isolation back to the X-former.

I take it that you can do this, at least in your area?

well yes, we can. there are some power co. guys that get a bit cranky, due to thier own internal rules that state THEY are to be the only ones.
Myself, I have reasearched the legislation here down to a state ( I am in Vermont) statues that basically say that any malicious tampering of utilities is unlawful.
I cannot wait for the local utilities to schedule every disconnect/reconnect, meter pull etc, I would not make a living very easy chasing them ( they can be rather non-committal) so I do as i please, but I usually fess' up as to the work done , lest they thing there is cause for such tampering.


Anyhow, thanks for the insight over there,

one more thing....

what does power cost there?

we do KWH ( kilo-watt hours) here


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#132718 - 08/22/01 04:15 AM Re: U.K. Residential service entrance
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
 Quote:
Originally posted by sparky:
Thanks, sorry for the fuss. The 'dual-usage' of a conductor as both N & G h


No problem. The various sytems used often create cnfusion for the uninitiated here, along with the conversion process of recent years.

In my area (Eastern Energy) all of the LV distribution systems have now been converted to PME (i.e. the extra ground rods have been installed by the utility), but there's no obligation for anyone to change their existing grounding arrangemets. It simply means that grounding to the neutral is now available as an option for everyone.

Note however, that our IEE Regs. specify stricter bonding requirements for water, gas pipes etc. if a house uses PME grounding, to safeguard against the effects of a lost incoming neutral.

 Quote:
I cannot wait for the local utilities to schedule every disconnect/reconnect, meter pull etc,


The open layout of our residential service entrance coupled with the all-insulated design of many domestic panels means that it's sometimes possible to do a "hot" changeover and avoid a utility call-out, which is billed at about 30 pounds (U.S. $45) in this area.

If the service fuse has to be pulled, I usually try to get everything ready for the swap and get the guy to wait 20 mins. or so so power can be restored quickly & without a second call-out fee. Most of the "meter men" in this area are happy to do that in exchange for a coffee/cold drink and the chance for a quick break and a friendly chat. Probably different in our big cities these days though.

 Quote:
one more thing....
what does power cost there?


Electricity's one of the few things which has remained stable in the last few years and hasn't soared in price.

From my latest bill:

Standard cost per kWh 6.51p., 9.8 cents

Night rate 2.78p., 4.2 cents

Plus standing charge £9.88, $14.82
per quarter (3 mo.)

Night rate operates midnight - 7AM in winter, 1AM - 8AM in summer.

This is the Economy 7 system. The basic tariff has a slightly lower quarterly charge, but the full cost per kWh 24 hrs.

Prices vary slightly in other regions,but aren't much dfferent.

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#132719 - 08/22/01 04:30 AM Re: U.K. Residential service entrance
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
P.S. Forgot to mention that you need to add the 5% tax to all those prices. Along with gas service and other domestic fuel, this is the only sales-taxable item which gets a lower rate than the standard 17.5%.

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#132720 - 08/22/01 09:58 AM Re: U.K. Residential service entrance
kent Offline
Member

Registered: 08/16/01
Posts: 27
Loc: Sweden
It’s sounds very similar to our system (placing of meters and such). I posted a picture of a Swedish service entrance. This is a rather old one but it’s typical. Big black thing to the right, meter. Below it main fuses and a main switch. In the fuse panel phases are located top to bottom (1,2,3). This particular panel is divided in four 3-phase groups and 9 single. The little box in the middle is a GFCI. This particular service is a bit odd. You can se 3 cables (old nasty steel shielded ones) enter at the bottom. One is from the power company junction in the street the other 2 goes only through the meter panel and down the street to the two neighbouring houses. Very funny I haven’t seen this type of connection before.



[This message has been edited by Webmaster (edited 08-22-2001).]
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#132721 - 08/22/01 02:30 PM Re: U.K. Residential service entrance
Bill Addiss Offline
Member

Registered: 10/07/00
Posts: 4196
Loc: NY, USA
Kent,

I had to copy the picture to our site to get it to display. (And I did a little editing)

Many times with the Free Websites they do not let you access a single file like that, presumably because they cannot attach an ad to it. Hopefully We'll have something available here soon where images can be uploaded to the Forum. (It's on the list of things to do) Anyone can still send pictures to me and I will see that they get posted.


Bill
Bill@Electrical-Contractor.net

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#132722 - 08/22/01 02:42 PM Re: U.K. Residential service entrance
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Kent:

I've never seen a service taken into a house then continued on to other premises. Very strange!

What type of fuses are those in your picture? They look as though they're similar to the older American types fitted on an Edison screw (light bulb) base.

We've never used that type of fuse here.

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#132723 - 08/22/01 04:53 PM Re: U.K. Residential service entrance
sparky Offline
Member

Registered: 10/18/00
Posts: 5545
Kent;
fairly scary looking!
What is the thing on right of the the box below the meter, bettwen all the stickers. Is that a switch?

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