Electrical-last stage

[ac1951]

When I've completed the modifications to the electrics as follows: Split Kitchen off onto it's own ring main + additional sockets Additional sockets on rest of house ring main Seperate feed for CH boiler Install Elect cooker point Interconnected mains powered smoke detectors Update equi-potential bonding New consumer unit.

So now I have all the new wiring connected to a consumer unit that has no power to it. Existing wiring (lighting and ring main) connected to old consumer unit with circa 10mm tails connected into Meter.

Can someone tell me the preferred way in which to manage the change over ? Need old tails dropping out of Meter and new tails from new consumer unit connecting to Meter Need to have main Earth connection from Consumer unit coonecting to incomming cable sheath. Do I just the Elect supplier to send a man and what paper work will they expect before responding (if any) or what paper work (if any) will the man require.

Should I move the circuits from the old consumer unit to the new before whoever comes to move the tails ? What other pre-requisites do I need to have completed.

thanks in advance Andy

[Andy Wade]

Contact your supplier to request connection of new meter tails and earthing conductor. They should be able to give you a definite appointment day and whether morning or afternoon. Before they are due to arrive, isolate and transfer the remaining circuits over to the new CU and complete any remaining testing and form filling. The old CU will now have no outgoing circuits, so you may as well leave its isolator open, but don't attempt to disconnect its tails yourself. Arrange independent temporary lighting if necessary using batteries or a portable genny, etc.

When they arrive they'll check your paperwork, possibly have a look round, then disconnect the old tails and connect the new ones. While the main fuse is out be sure to take a look at it so you know for sure what rating you've got.

Of course this is an excellent time to get a supplier's isolator fitted, so that you can make future alterations safely without having to bother them. Enquire about this when booking the appointment, AIUI some suppliers will do it FOC, some charge, others don't offer it at all.

It will usually be someone from the meter operating company that does the work. They might send a woman.

They will want some evidence that the new installation to be connected complies with BS 7671. If you provide an electrical installation certificate together with its schedules of inspections and test results you should have no trouble at all. Testing should include all the old circuits that you've transferred across.

All the info you're likely to need on inspection and testing can be found in the OSG (chapters 9 & 10, and appendix 7). Blank forms can be downloaded from the IET website.

If they fail to turn up when expected then you can get power back on, temporarily, by connecting your new tails into a 30 A outgoing way in the old CU (use a Henley block or similar to reduce the 25 mm^2 tails down to 6 mm^2 for this, and be careful about how much load you draw). Remove any such makeshift arrangement before the next appointment time.

HTH, hope it all goes well - do report your experience here.

[George (dicegeorge)]

i searched

for OSG and IET but found nothing...

after a while i found

searched that for OSG it talks about 'The OSG' but doesnt say what or where it is....

can we have a links page at

new learners like me!

I want to rewire my house legally, which means finding out what the regualtions are on rewiring kitchens, bathrooms and everywhere...

i dont want to do loads of work and then be told to rip it out because it has to be done with a certain certificate!

george

[Andy Wade]

Oh sorry, I do sometimes spell it out - it's the IEE's "On-Site Guide" - a useful reference book:

don't buy that one though because there'll be a revised 17th edition version out before long.

[Andrew Gabriel]

What you can do temporarily is to feed the new CU from the highest current way in the old CU, being careful not to overload it (no electric showers or cockers -- trip any such circuit off in the new CU).

It's too late now, but the other way to do it is to install the new CU with just a builder's socket connected, and get them to transfer the tails to that (very simple inspection report). Then temporarily feed the old CU from one of the ways on the new CU, and transfer/test the other circuits across one at a time at your leasure.