Lighting in Twin - cpc addition

[DJM]

OK this is a temporary fix prior to a proper re-wire of the lighting circuits, but SWMBO want breakfast room decorated whilst kitchen is being done (as if I don't have enough to do), so don't shout too much please.

New 17way split load being fitted as a result of kitchen work, and ready for more extensive house re-wire. (Electrician coming to do all that). But lighting circuits for rest of house wont be moved in this update.

Currently Light circuits in twin and SWMBO wants a particular light fitting in breakfast room which is metal.
So my question after all that waffle is

Can I run a single from MET block to Breakfast room ceiling rose and switch, and if so what size would be suitable?

 

[securespark]

You should at least run a cpc, following the same route as the twin cable, running it back to the earth terminal in the CU.

But if you're going to do this, you may as well R/W.

 

[Adam_151]

If you can get a cable back to the board, why not just join the loop together at the breakfast room fitting, and put a new feed to the fitting and replace the switch drop as well, That way, when you come to have the lighting circuits re-wired, you don't have to touch the breakfast room one and it stays nicely decorated

EDIT: make sure you leave a bit of slack at the board end, so the board change doesn't require crimping the new cable!

 

[DJM]

My preference would be to go back to the CU, but 2 reasons why this isn't practical

1) I am paying the electrician who is fitting teh 17way to come back early next year and do the work for the twin lighting and removal of VIR so don't really want to have teh work done twice,
2) The CU these are connected to is very old and I dont want to touch it.

I had intended to run T&E to the switch so that no new chasing out was required, but was going to run cpc to ceiling rose from MET. As MET is bonded to CU, and single would be properly labelled at both ends, I assumed this would be OK.

 

[Adam_151]

Not massivly keen on this tbh

Just realised who you are from that picture... I remember the thread!

Anyway, new feed to the breakfast room light, and feed it from an FCU spured off the rfc breaker on the grey wylex board?, leave slack for now, and it becomes its own circuit when you have a new board installed

 

[DJM]

I'm sure you do remember the thread, and I thank you for your contributions on it. Helped a lot

Just as an update, EDF did eventually turn up and were very unhelpful, but have moved meter onto lower board making space for new CU. Large Grey Wylex is being removed and circuits being moved to the new 17-way in a couple of week. New kitchen radials for hob (10mm) and ovens (2 off 4mm) from 17-way at the same time. New 8-way MET with bonding updated. Small grey wylex with SWA remains but repositioned.

This leaves the old MEM which mostly wont get circuits moved as they will be rewired once the kitchen is finished.

End result is
1) run new circuit just to breakfast room from new CU now - which wont fit electricians time table or ours
2) leave with old fittings and suffer more mess later
3) run T&E to the switch and a single cpc back to MET which will be replaced by new lighting circuit early next year and no redocorating

 

[Adam_151]

I suppose you could drag in a 4mm² single earth if you really wanted to, but I don't understand the point

Drag in a 1.5mm² T+E instead, just an extra existing circuit for sparky to put on the new board, and being just a single point will be as easy as pie to test out.

I can't see why this would not fit with timetables? its going to be no harder for you, and very quick for the electrician

 

[DJM]

Thanks for the replies Adam.
The light is currently the last in the run, with access via the other rooms fittings relatively easy, but direct to CU more complex due to concrete floors. Electrician has already expressed a preference for light circuit routing and and I can see his point. I don't really want to hack him off by forcing the issue.

I can relatively easily pull through 1.5mm T+E to the switch from the rose, and I can live temporarily with a partially concealed single outside of room (in an area which needs redecoration anyway) to CU. This will still allow electrician route he wants, get the right cable in place for switch so no re-decorating and stop SWMBO whinging.

I grant you it's not the best solution, but it does serve the purpose. I will check with electrician, if he's happy with a different route and if go that way.
Thanks

 

[Adam_151]

Ah, I see your point now, shouldn't really run the cpc a different route to the live conductors AFAIK (couldn't quote the relevant reg offhand though), but I suppose the circuit isn't compliant anyway... (shouldn't really be thinking like that!)

No chance of getting 'er indoors to stick with a pendant for now?

Temp feed from an FCU off a S/O in the room next door that needs redecoration?

 

[DJM]

No chance of getting 'er indoors to stick with a pendant for now?

That shows you've never met her. When she's made up her mind then woe betide anybody standing in her way. Especially if they put 'little' things like rules, regulations or my safety in the way. She' lovely reall (just in case she logs on and reads this)