Domestic Installer - a scheme that covers general electrical installation work in UK domestic properties only

 I see nothing especially magical about 3 phase - in much of the world domestic incomers are 3 phases by default (Southern Germany for example ). In such places, immersion heaters and cookers are commonly fed with more than 1 phase. 
I'd like to thing any domestic installer capable of say a UK CU change, ought to be able to handle the modest complication of a couple of extra live wires, at least as well as they handle things like TT supplies, rare in larger towns, or sub-mains to sheds and garages, like all things, if they don't do it that often, a quick flick though the book ought to refresh. Most domestic loads and final circuits will remain single phase.

Mike. 

In some parts of the country the policy seems to be to install 3-phase for domestics by default now - to cater for future EVs, Heat Pumps etc.

Some network faults (lost Ns) can potentially put 400V or so across single phase supplies - so that's something that the equipment and procedures should handle anyway.

  - Andy.

The CPS's say Domestic Installer is only 230v in dwelling like house/flat thus if 3PH gets fitted this will leave people having stern conversations.

https://niceic.com/for-the-trades-1/professional-standards/schemes/domestic-installer-scheme/

For myself should not be an issue if three phase or single phase. Reason being the person carrying out the work must be "Competent" for the work to be undertaken.

Reality is should one expect that the "Electrician" and I use that word loosly since it has no legal protected status be a lesser "Competent" person than somebody carrying out a small retail/commercial installation?

We all know the race to the bottom, and hey ho its only a house, so crack on, get it wired what can go wrong!

Cheers GTB.

The CPS's say Domestic Installer is only 230v

where does it say that? (seems odd, since part P will certainly cover many 3-phase (even some 460V split phase) installations).

   - Andy.

GTB said:

crack on, get it wired what can go wrong!

Phase rotation? I think that is the only extra test.

The practical scenario in my C&G exams was a flat fed from a 3-phase intake in the basement, so we had to demonstrate our capability for initial and periodic inspections. It was not a problem.

All that said, I would not advise a domestic installer to start installing 3-phase without some training on the basis that if something does go wrong, it is more difficult to avoid blame.

Chris, totally understand where you are coming from, so question is did the domestic installer have no understanding, exeprience and knowledge of three phase? Simply because he is Domestic installer. Or did that domestic installer via their NVQ formal training etc at one point in early career fully understand about three phase and yes do the check on phase rotation and has simply "Forgotten" about it all, hence needing a little reminder via CPD.

Or are we saying that those persons carrying out domestic work are not cpable of doing anything else.

Cheers GTB 

"The CPS's say Domestic Installer is only 230v "
Seems like a serious weakness of the Nic DI scheme, if that is true, - its a totally spurious limit, and they might just as well say they can only work on 5/6A lighting ccts and 13A socket stuff for example and not do CU changes or cookers and showers, as those are probably higher risk items.

Think more generally, then as observed it is likely to have to change.

Mike.

mapj1 said:

"The CPS's say Domestic Installer is only 230v "

Three-phase TPN with earthed neutral is only 230 V to Earth ... in fact, as discussed elsewhere, the supply is still derived from 230/400V TPN supply.

GTB said:

Chris, totally understand where you are coming from

I was really making the point that with the exception of phase rotation, all the other procedures are the same. There are, as Sergio said at the beginning, simply more of them.

I don't see that wiring up say an estate agent's in the high street is different from domestic, although a restaurant next door might be.

Perhaps instead of, "domestic installer", we should have T&E only?