**CU Changes And YOU**

[m25maintenance]

earth and neutral, i think its earth, then line and neutral joined together so eathe to line neutral so not to damage equipment

 

[nadger]

no thats not the one Lenny sorry. on your link at the very end there are 4 more examples of "best practise" pdf's. the one im looking for is the one on the right, its all about our responsibilitys and what tests we need to carry out. The link you posted is for consumer unit changes where the lighting circuits dont have a cpc.

If i remember correctly there were 2 links in the post i cannot find and the one i want was accompanied by the one you just posted for me if that helps?

 

[JUD]

earth and neutral, i think its earth, then line and neutral joined together so eathe to line neutral so not to damage equipment

Had you been sniffing the barmaid's apron when you wrote this??

 

[JamesBrownLive]

no thats not the one Lenny sorry. on your link at the very end there are 4 more examples of "best practise" pdf's. the one im looking for is the one on the right, its all about our responsibilitys and what tests we need to carry out. The link you posted is for consumer unit changes where the lighting circuits dont have a cpc.

If i remember correctly there were 2 links in the post i cannot find and the one i want was accompanied by the one you just posted for me if that helps?

Still not 100% sure which one you want, but following this link will take you to a page where they can all be downloaded:

Best Practice Guides | Electrical Safety Council

Have fun

 

[nadger]

sorry i should have posted to say i'd found it on their site.

the one i wanted was the "consumer unit changes in domestic properties"

thank you for your help though, much appreciated.

 

[rs250250]

This is a great thread and very informative although I have 1 question. Forgive me if it has been discussed elsewhere as this is a big forum

I am anticipating doing several additions and alterations to an existing installation such as adding sockets and lights. The consumer unit is a 16thED MK nicely done although I am upgrading the tails and also new water bond as this looks to be absent. Condition of wiring is good overall. Being as the existing board is split with 1 RCD + one half non RCD protected do I need to upgrade the board? Or do I have to replace the board to bring it in line with current 17th ed? Guess it would be easier to do that and just issue an EIC for the whole job!

I was thinking if the client does not want to pay for a board change (as most do not) I could use RCBO's.
I know that any circuits I add that are for example, chased in less than 50mm will need to be RDC protected so can I swap circuits around i the consumer unit to achieve this?

Can anyone clarify this for me.
Many thanks

 

[Spudnik]

If the CU and existing wiring is in good condition then, any circuit you alter (that is on the non rcd side), can be protected with an RCBO.

 

[fozzy]

would you not carry out a full test before changing the cu to highlight any existing problems with the installation.you can then make the customer aware of any additional works and costs to the job.if you go ahead without any inspection and there are any faults uncovered you should then put in right.

 

[Spudnik]

Have you read the first post?

 

[Ponty Massive]

If your linking the L+N and testing them between earth, why are you only using 240v instead of 500v?

Cheers

 

[Spudnik]

No reason not to use 500V.

 

[Ohmyword]

Not certain if this is the correct Thread for this question/query - but to quote a statement from the "Regs Thread" :- Meter tails are part of the consumers installation and are to be provided by the installer. Meter tails must be sheathed and insulated or if insulated only must be enclosed in trunking or conduit. Meter tails must be 25mm.
Is that last sentence applicable to every mains distribution board in the U.K? (As a minimum size I assume?)
I know of one electricity supply co. with it's own meter fixers who only use (max.) 16.0 m.m. tails from cut-out (main service fuse) to meter. This is in West Cornwall area.

 

[mandrews]

previously over the years i have mounted ccu's on an mdf board.
with cut out on the back of ccu and mdf board,
for cables to enter,
I have seen NICEIC testing inspection dvd with Tony Cable saying its a fire risk to have a hole in the mounting board...




Attatched are photos of two diffrent NICEIC domestic installers 17th edition boards taken of google images
with the mounting board and an opening to show what i mean.


the only regulation i can find close to what i need to know is.


BS 7671 134.1.6


Electrical equipment likely to cause high temperature or electric arcs shall be placed or guarded so as to minimize the risk of ignition of flammable materials.


does this mean if the wooden cut out is larger then the opening on the back of ccu this would reduce if not stop any sparks coming into contact with mounting board and would meet all requirements to BS 7671

 

[Jas0n7]

Because if you have bad readings Earth to Neutral then you might have problems with RCD's holdinig in.

 

[gpz900jim]

maybe its to rule out neutral to earth faults which would not show themselves up until the rcd was switched on