CU Change and extending circuit wiring

d3jpt · May 9, 2011

I am changing my home CU for my NIC inspection. At the moment i have a rewirable fuse CU in a 1960's house so thought its about time its changed. On initial inspection everything seems in order, ok it all need to be brought up to 17th standards and none of the lighting circuits have an earth but it doesnt look too bad.
One thing is though there isnt enough slack on the cable and every circuit needs extending to fit inside the new CU. My question is as it needs to be inspected is what would you use to extend the cable for each circuit? I was tought that red/blue/yelllow butt connectors are fine but just not really sure about these. what would the NIC say?
cheers for any advice

telectrix · May 9, 2011

first, if all cables come from above, can you not fit the new CU higher up.? second, if not, i would get an adaptable din rail box with din rail terminals and extend using that. however you extend, the joints must be enclosed in a box or trunking or similar.

Electricalserv · May 9, 2011

d3jpt said:
I am changing my home CU for my NIC inspection. At the moment i have a rewirable fuse CU in a 1960's house so thought its about time its changed. On initial inspection everything seems in order, ok it all need to be brought up to 17th standards and none of the lighting circuits have an earth but it doesnt look too bad.
One thing is though there isnt enough slack on the cable and every circuit needs extending to fit inside the new CU. My question is as it needs to be inspected is what would you use to extend the cable for each circuit? I was tought that red/blue/yelllow butt connectors are fine but just not really sure about these. what would the NIC say?
cheers for any advice

There are numerous ways to extend cables. Aslong as they are mechanically sound. Alot of people use crimps. Forgot what the industry name for them is.

malcolmsanford · May 9, 2011

^^^^^^ as above IMO far better than crimps in this situation.

Tel's suggestion

High Tower · May 9, 2011

adaptable and din rail
adaptable and wagos
trunking and crimps

take your pick

topquark · May 9, 2011

If you go the route of wagos, watch the current carrying capacity of the wago is adequate for the cables maximum rating (even if the breaker is considerably lower in value).

d3jpt · May 9, 2011

Cheers for the sugestions, The CU is in the garage which is attached to the house all the cables are coming through the wall.
I will look into the adapatable din rail, Just got to make sure its right.

telectrix · May 9, 2011

and if you use an adaptable box you can label i german " Achtung, Gerfingerpoken Verboten"

nickblake · May 19, 2011

/I know thread is a week old but ive used wagos to extend the wires here's a pic

and before you say it it had grommits on when i finished it and i had ran out of green and yellow wagos , if you 've not used them before then these are the push fit din connectors

Octopus · May 19, 2011

nickblake said:
/I know thread is a week old but ive used wagos to extend the wires here's a pic View attachment 5670and before you say it it had grommits on when i finished it and i had ran out of green and yellow wagos , if you 've not used them before then these are the push fit din connectors

Nice and neat, how long did that take you?

Phil · May 19, 2011

nice job there Nick. thats my prefered way of extending when doing a cu change

topquark · May 19, 2011

nickblake said:
/I know thread is a week old but ive used wagos to extend the wires here's a pic View attachment 5670and before you say it it had grommits on when i finished it and i had ran out of green and yellow wagos , if you 've not used them before then these are the push fit din connectors

Very neat Nick. You can do my hair anytime (not that I've got any left).

ian · May 19, 2011

How good does that look. i use an adaptable box too. although its neat, i wish i could say its that neat.

ian

Des 56 · May 19, 2011

Nick may have now raised the standard of these cable extensions

We will all be trying to match him for quality pretty soon then

telectrix · May 19, 2011

nickblake said:
/I know thread is a week old but ive used wagos to extend the wires here's a pic View attachment 5670and before you say it it had grommits on when i finished it and i had ran out of green and yellow wagos , if you 've not used them before then these are the push fit din connectors

nice neat job, nick. just think it would have looked so much better with red/black cables .LOL

Goody · May 19, 2011

nickblake said:
/I know thread is a week old but ive used wagos to extend the wires here's a pic View attachment 5670and before you say it it had grommits on when i finished it and i had ran out of green and yellow wagos , if you 've not used them before then these are the push fit din connectors

You have set a standard there. Experience shows!

nickblake · May 20, 2011

thanks for your comments guys im realy touched , mudock wanted to know how long it took , it was about 2 hours ,the house was an old stone house with an extension and it was decided to move the CU to the utility where the extension was and to extend the existing cables to the new CU , the other end now has a hi integrety dual RCD board for the power and a 8 way RCBO loaded board for the lighting

/its not quite finished yet i need to go back and sor out the functional earth wires , the nice thing i find is as i work for myself im not under pressure i take as long as i want , i do tend to be picky if i dont like how it looks then ill take all the wires out and start again , drives my apprentice nuts , i have to admit some times you just can make them look neat

again thanks for the comments guys

Engineer54 · May 20, 2011

Nice, neat board and extension box installation Nick. Did you mark or leave a circuit identification schedule in the extension box for future referral?? The only minor improvement i can see that could be made, is the use of crimped ferrules on the thin multi stranded neutral cables from the RCD devices. ...Again a nice installation Nick.

nickblake · May 20, 2011

Engineer54 said:
Nice, neat board and extension box installation Nick. Did you mark or leave a circuit identification schedule in the extension box for future referral?? The only minor improvement i can see that could be made, is the use of crimped ferrules on the thin multi stranded neutral cables from the RCD devices. ...Again a nice installation Nick.

Yes i did you cant see it on the pic each of the cables is marked and there is a list on the box lid , the neutral wires on the lighting board didnt need ferrules the wires had been tinned so they were installed with out ferrules , the main board did need them ,when i go back to sort out the functional earth wires then the ferrules will be installed , these i normally do but forgot to take them them with me on the day when i did the board , i normally keep them on the van but was using them at home totally forgot to put them back on the van

thanks for your comments engineer 54

mattmoo1974 · May 20, 2011

nickblake said:
/I know thread is a week old but ive used wagos to extend the wires here's a pic View attachment 5670and before you say it it had grommits on when i finished it and i had ran out of green and yellow wagos , if you 've not used them before then these are the push fit din connectors

Thats well Preddy Nick
Hat off to you mate

midgetman · May 20, 2011

yes good work mate - ooooozes quality

Antman · May 20, 2011

Great install that fella

ridemx27 · May 22, 2011

Iv been asked to do a job like this of relocating and installing a new cu an again has no cpc in lighting circuits cables are pvc stranded just wanted to ask peoples views on this as i wouldnt normally do it but when a customer cant afford to have the circuits rewired yet but needs the cu accesable as its currently under the first step of his stairs and wants the rcd protection for safety i cant see a problem with doing it as its still making the installtion safer and giving the 30ma protection between the circuits and any extraneous earths such as a light sw and raditor. All other circuits in the property have cpcs. As far as im concerend my cert is covering the cu instatall, extentions to circuits and to prove test results and visual inspections are satisfactory am i suppose to tell the customer no you can have a safer cu as u have no cpc in ur lighting circuits or am i right in doing the job and advising on the situation ? just intrested to hear what people think really ?

nickblake · May 22, 2011

you can change the consumer unit with lighting circuits with no cpc ,just ensure that there are no metalic light fittings and identify the board that the lighting circuits have no cpc there is a link changing an consumer unit with lighting circuit with no cpc its on here some where will explain all ill see if i can find it or some one will add the link im sure

mattmoo1974 · May 23, 2011

If know 1 posts the link by later Ridemx iv got it some where, Im just off out the door so if know 1s replyed by this evening i ll find it for you.

nickblake · May 23, 2011

Found it matt heres the link for ESC best practice guide No 1 well worth saving to your PC or printing it off

http://www.esc.org.uk/industry/industry-guidance/best-practice-guides/