theoretical modernisation of an old installation

[jprice91]

I have recently bought a large Victorian house. The existing electrical installation comprised of two Wylex six way fuseboxes (cream plastic 100A each) and a smaller 2 way metal MEM box which had been added for the garage. We decided to have a new large modern CU installed, and since the existing cabling checked out OK (by the electrician) this has been done and everything is up and running and the place now has RCD protection etc...

When I was weighing up options on what to do however, I drew this up as a potential way of using and updating the existing CUs (minus the MEM box). Although we ultimately decided to go for one new large CU, I am still curious as to whether this setup (assuming it was installed correctly) would have met regulations.

Untitled

• jprice91
• 26 May 2014
• 1

CIRCUITS:

WYLEX 1

1 - GARAGE LIGHTS (5A BREAKER)
2 - ATTIC LIGHTS (5A BREAKER)
3 - 1ST FLOOR LIGHTS (5A BREAKER)
4 - GROUND FLOOR LIGHTS (5A BREAKER)
5 - ATTIC RADIAL (25A BREAKER)
6 - GARAGE RADIAL (25A BREAKER)


WYLEX 2

7 - KITCHEN LIGHTS (5A BREAKER)
8 - BASEMENT LIGHTS (5A BREAKER)
9 - BASEMENT RADIAL (25A BREAKER)
10 - KITCHEN RADIAL (25A BREAKER)
11 - 1ST FLOOR RING (32A BREAKER)
12 - GROUND FLOOR RING (32A BREAKER)

MODERN CU

13 - SHOWER 1 (40A RCBO)
14 - SHOWER 2 (40A RCBO)
15 - COOKER (16A RCBO)

I am not an electrician, which is why I decided to have the whole setup replaced professionally, so please point out but forgive any obvious mistakes I've made here as I'm just interested as to the ins and outs of what is OK/not OK about this 'theoretical' set up.
Thanks for your time!

 

[AndyPRK]

Circuits should be arranged so than one rcd should have upstairs lights and diwnstairs sockets and the opposite on the other rcd.

To minimise inconvience, for safety. Etc.

So not ok as you have it. You could have swapped circuits between boards if the cables were long enough but you may as well have a new tidy install.

 

[RF Lighting]

Other than being a bit messy, I can't see any real problems with it.

 

[EFLImpudence]

I would swap some of the circuits around if the cabling would allow.

When you say 'breaker', were they the plug-in ones?
If so, you are better off with the new unit.

If they are, in fact, fuses and you don't mind the odd replacement then, yes it would be fine.

 

[jprice91]

Thanks, its good to know it would have worked at least (with the appropriate tweaking)

It was plug-in breakers, are these bad? The correct covers were installed for them so they did fit OK.

However, I am happy with the new CU, all certified and nothing to worry about.

I've kept most of the old MK sockets, the type with the 4 screws, 2 top and 2 bottom. The electrician said they're probably among the best sockets ever made, and there's no point replacing them as they're working. Just going by the feel of them, I think he was right, they have a great action on the switch compared to some of the newer cheap plastic things you see. Great retro look too.

 

[OwainDIYer]

5 - ATTIC RADIAL (25A BREAKER)
6 - GARAGE RADIAL (25A BREAKER)
9 - BASEMENT RADIAL (25A BREAKER)
10 - KITCHEN RADIAL (25A BREAKER)

what's the cable size for those 25A radials?

 

[ericmark]

Nothing wrong with it. I would also ensure safe lighting, but using emergency light fittings would be far better than two RCD's or more for the lights. I have one at top of landing and garage so we can see to reset RCD or MCB if required.

 

[jprice91]

Sorry, I've made a mistake there, the breakers were 20A, 25A plug-ins aren't available for the Wylex boards. The cable size is old imperial 7/029, roughly equivalent to modern 2.5mm I think!