Thanks for the unput, So you are saying it's not *necessarily* true, but just possibly true, yes?
Wish I knew the best way to maximise my chances of avoiding having to pay for an entirely new 2nd gas supply... I bet tsomeone out there who knows the answer.
JBW, Sorry: I forgot to state the url for the photo of the meter box:
members.aol.com/JIM1836A/leccy1.jpg
Cheers.
A and B are commonly called Henley Blocks, after the name of the makers, as in Hoover, and they have already been used to separate the original supply cables from the meter into two separate distribution devices you have installed. The two devices being the white consumer unit at the top of the picture, and the bottom larger grey MEM single fused isolator switch. I also see that a further tapping has been taken from the larger isolator in to the smaller one to further split the supply to something else.
If you install a 2 core X 25 mm csa' SWA cable in to the area around which is shown in your picture, and also install a 100 Amps Rated, Double Pole Isolator Switch where the two Henley Blocks are currently positioned, then connect the SWA to the isolator switch, properly, and allow two tails of the same csa' (cross sectional area) as the SWA conductors (25 mm csa') so the whole installation can be ready for connection by the leccy co. to their head end. Then I think you'll have broken the back of creating a sub mains supply for the new flat.
In the new flat you'll need to install a head of some sort, but the leccy co. might actually do this part for you, so ask them first. Now you'll need to rewire the whole flat from its own totally separate consumer unit, leaving the same sized tails from it as the SWA cable. Then the leccy co. can install their new meter and connect the newly rewired and fully safe and secure flat to it. Remember that they will fully test it before they make the supply live, so make sure it is all up to scratch.
With a SWA cable of the correct rating already in place between the two supply positions, the leccy co. will be able to connect directly to the main fuse on the existing head end from your 100 Amps isolator switch with the cable tails already attached for them. From the 100 Amps isolator to the new head end in the new flat. From the new head end in the new flat to the new meter. From the new meter to the new consumer unit sitting beside, below, above the new meter.
By doing all this by yourself, and making sure it is done properly by yourself, you are taking the bulk of the work away from the Leccy co's. contractors. So it does help in keeping the full bill from them down a bit. If you find a good supplier of good quality materials at reasonable prices, then you could work out to have saved a good few pints worth of money.
That's all extremely helpful; thanks!. Just one thing is baffling me though: If I do what you suggest, the the second flat's meter (not yet installed) will be taking it's feed via the house's original meter (shown in the pic), yes?
If that's the case, then the original meter (currently located in the ground floor, inside Flat A) will record the amount of juice used by Flat A and Flat B together.... That could result in the resident of flat A reciving a bill for his own consumption, plus the other flat's consumption.....
I'm sure you must have considered this, so I've probably misunderstood something. Could you could explain?
J"Stefek Zaba" wrote | 100A fuse is the last bit of protection they apply to their cables. | If you decide to suck on the Big Red Wire,
Or brown or blue or black wire :-)
Owain
Possibly, but you are entirely in Transcos hands here. It all depends on the pipe size rising up the building and the unseen length underground. If its an old pipe they may want to run in a new supply back from ther street main. They may just decide to run in a bigger "shared supply" and renew the supply to the rest of the house but its their call and though you might get a sympathetic surveyor you just as easily won't
Instead of asking until "someone" gives you the answer they think you want to hear you should start the estimating route and fins out what the Engineering answer is. It doesn't matter what group readers say it isn't their call.
No. They will remove the main fuse and connect the new sub mains supply cable to that directly, not through the meter. If you look at the top of the main fuse on the head end, you'll see that it has two indents for cable entry. One is already taken by the tail for the existing meter, but the other is free to be knocked out and another new cable connected to it.
Once they are happy that the new installation is safe and fully operational, they will re-seal the main fuse. You can then control the new supply with the 100 Amp isolator switch you fitted for the new sub mains supply to get connected to.
Read above reply.
I did already. :-) LOL
I hear what you're saying, but so often I've found that things aren't as cut and dried as people make out. I've found that sometimes it pays to keep looking for the hidden route, the lesser known path, the trade secret etc. Sometimes it comes down to a decision whether to keep looking, or settle for the well-trodden, official path. Sometimes deadlines force you to settle for the latter. Conversely, sometimes it pays off to keep looking, keep asking, etc.
J
Thank you for the help. Do you happen to know what sort of tests they use to ascertain whether the wiring cirquit is 'safe'? If I knew that, I could perhaps run the test mystelf before they come on site.
J
One note on this - this used to be common practice, but it is becoming less-so now, and there are technical reasons that go hand-in-hand with this.
If the supply is in another flat, they would have no independant means of isolation, and the "new" supply would require a seperate meter point administration number (MPAN) creating for it.
Getting an MPAN is like pulling hens' teeth, and may consist of several components that only an electricity co. may be able to provide, such as the load characteristics of the proposed use, and tariff information.
Any submain over (IIRC) about 2 metres should have a fused isolator - you're not supposed to rely on the fuse in the electric companies' equipment. The fuses in this isolator should be at a lower rating than the fuses in the electric co's equipment to provide discrimination (in other words, your fuses blow first)
There may also be a legal aspect to the electric co. fitting a meter to the end of a submain - they may be seen as accepting responsibility to repair the cable if it should fail at some point in the future. On a safety related note, their jointers are not allowed to work on cable for which they have no documentation.
There are some anomalies as far as submains are concerned, but these (to my knowledge) all relate to rising mains in large offices / buildings. The rising main belongs to the building owners, and it is down to them to maintain it. In order to get a supply to a newly seperated part of the building, their own electricians fit a tap-off box to the rising main, lay a submain to the new location, and will typically fit their own cable head / cutout.
As far as tests are concerned, test-notes used to be requested for new supplies (in our area at least), but these are now being phased out - the electricity co. warrants that the installation that belongs to *them* has been installed in accordance with regs, but anything beyond that point on the customers side is the *customers* problem. A new installation may typically be terminated into a double pole isolator, and the customer has to get their own electrician to connect their side to the supply.
The electric co. does have the ultimate sanction of being legally required to render a supply safe if its in a dangerous condition, but that may be by simply removing the main fuse, or in extreme cases (vandalised / vacant / fire damaged properties) by disconnecting the supply externally.
If you want buy the test gear they use, then go ahead, but it is not cheap bits of equipment like a simple multi-meter. They test for correct earth-loop impedance, voltage drop across the mains conductors under differing conditions and other safety device tests. They are very commonly strict on exposed conductors showing at the terminals of any connections, so make sure you cut the insulation to just the right amount for the copper to be gripped tightly under both the grub screws, leaving the insulation sitting as close as possible to the terminal itself. Try not to expose the bare copper at all.
'Nuff said! That's why so many (including me) are moving oop North! Or anywhere in fact that is outside the south-east. Here you still get genuinely fair traders, like it used to be across the country 40 years ago. The south-east is cowboy country, no matter what you need. I blame Londoners.
MM
As Colin Wilson has already said, "they" no longer routinely do any tests on a consumer's installation. In fact they haven't done so since the 1988 Electricity Supply Regulations (since superseded) came into force.
They will expect to see a fully completed and signed electrical installation certificate (as detailed in BS 7671) before connecting a new supply. To see what's involved you can find the blank forms at
everyone bothers with them at all now. Essentially a signature and address of their electrician so they know where to send the HSE if someone gets fried.
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