Photo's of my CU change

19 Jan 2007
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United Kingdom
Here's a set of photo's of what I did today.

If it had of been a new cable installation it would have been better, but there where a few cables that weren't long enough to allow the luxury of too much choice in the looming and setting out.

Picture 1

The old box was recessed, so I had to cut out some plaster and 10mm of brick. The little dremel and 30 minutes later.

picture 2

The old CU wiring exposed, I did that about 4 years ago (in a rush)

Picture 3

Time to get serious with the screw driver

Picture 4

The old CU off and the original render cavity beside the new cut area

Picture 5

Behold a new CU. Cable markers were left over from an LUL job.

Since the Circuits are A, B and C (direct, RCD 1 and RCD 2).

I labelled them as Circuit A 1st AA, 2nd AB, 3rd AC etc

Picture 6

The earth signal wires from the RCBO's in position Circuit A. 1 and 2 aren't friging long enough to terminate on earth positions 1 and 2.

So there on 15 (spare) at the moment. Wylex you tight sods, make them longer.

Picture 7

More of the same

Picture 8

More of the same

Picture 9

Cover on, labels sorted (MS excel with the cells sized correctly). Although you will notice they are slightly too small due to the printer bing dross.

Picture 10

Just cut too large a void for the CU to seamlessly fit, never mind a bead of caulk and redo the wall paper some time.

There are a few things wrong. The earth signal cables annoy me, and again due to being 2cm short there's a pair of earths on earth 9 rather than earth 4.

When I sort out my soldering gun I'll cut, tin and re terminate the factory neutrals on the neutral bars (I don't see why they need to have 5mm of core showing below the bars). I'll extend the earths to the correct point at the same time.

So if this site was Master Chef would I get past the 1st round :D

Flame suit on, so fire away :D
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On Wylex boards, I tend to relabel the earth bar so that it reads in the same direction as the neutral bar. It makes life a lot easier! :D
You need to unsleeve those RCBO earths.

They are functional earths, not CPCs, but apart from that it looks a nice job.
I've noticed that you have sleeved your RCBO earth connections in green and yellow. I do this too, but I was wondering if this is actually required, or whether in fact they should be cream? If so, why don't the manufacturers do this?
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I agree it looks like a nice jobbie.

My only comment would be if your not going to ID the circuit earth & neutral cables there is not much point in ID-ing the live.
I have come across RCBOs with gn/yel tails as well as cream functional earth wires, Square D Qoe range iirc.
It is easy enough to extend them by soldering a piece of wire to them and heat shrink sleeving over the join.
Failing that you can through crimp but I think can look a bit tat.
When I sort out my soldering gun I'll cut, tin and re terminate the factory neutrals on the neutral bars

Don't do that. The solder will creep under the pressure of the screw and create a loose connection.

Need to add the inspection/test label.
The 2 colour warning label is too small.
The 2 coour label is supplied by Wylex. Tell them it's too small.

As far as functional earthing is concerned, cream is listed in the regs as the colour used for identifying such conductors.

Finally, the C type RCBO's....are your EFLI's at the circuit destinations within spec for C6's?
Cooker cable looks thin in a C40 :eek: or is that an illusion?
the C type RCBO's....are your EFLI's at the circuit destinations within spec for C's?

If its covered by a 30mA RCBO then isnt the max efli 1666 ?

The neutral numbers dont correspond with earths or lives
With TN systems you should really be designing the circuit with the maximum loop values of the overcurrent protective device in mind.

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