Roger Mills wrote:

Yes, for TT a main switch and two RCBOs would be a good option, or
main switch with one MCB (lights) and one RCBO (power) for TN. I'd be
inclined to make the 'power' RCBO a 20 A one - RCBOs only come as
Type B and 16 A Type B might tend to trip on motor starting currents,

Hi again Andy,

Thanks for the above information. I'm still a bit confused!

From earlier discussions, it looks likely that my main supply is TN-C-S or
*possibly* TN-S.

I've looked at the MK stuff on TLC's website, and can't quite work out what
I need - not for a reasonable price anyway! Their split load CUs are 70-odd
quid +VAT before putting any innards in. Can you suggest a shopping list of

If you go the split load route, then you don't need the RCBOs and can
use ordinary MCBs for all the circuits. However as you have found; split
load CUs tend to be big and expensive.

bits which would give me MCB protection for lights and RCBO for power - and
be compatible with my mains supply - without costing an arm and a leg? [The

Does it have to be MK? If not, how about (For a TN supply):

http://www.tlc-direct.co.uk/Products/CMM4N.html
http://www.tlc-direct.co.uk/Products/CM7106B.html
http://www.tlc-direct.co.uk/Products/CM92003SP.html

price reference is the Screwfix garage enclosure for ｣37 - so I'm hoping to
get something which *doesn't* take out the lights when the RCD trips for not
too much more than this].

Your difficulty there is the price of RCBOs - one of them costs about that!

Cheapest (but not smallest) option may be:

http://www.tlc-direct.co.uk/Products...0slash80N.html
http://www.tlc-direct.co.uk/Products/CM7106B.html
http://www.tlc-direct.co.uk/Products/CM7120B.html

Although that still tops £50

Incidentally, my current thinking is to join the T&E to the SWA using an
adaptable box in the roofspace. This means that there won't be any joints
exposed to the weather, and the cable won't need chasing so deep into the
wall of the en-suite. Hopefully, I can strip the end of the SWA and fit the
gland in the en-suite, and then poke it up through the hole in the ceiling,
and then grovel in the attic to make the actual connection, which shouldn't
be too bad. Does this sound reasonable?

Goveling never sounds reasonable, bit if is what you have got to do.... ;-)


--
Cheers,

John.

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