some more 'cu change' questions....

[andart]

I have read all the threads on changing a CU but have a couple of extra questions I hope you can help me with:

1. The cable ends I have are just long enough for the new CU but not quite long enuogh to let me get all the earth connections in the correct order (to be honest it looks like a cats cradle) - what can I do about this?

2. the old set-up had 6 circuits on an old fuse wire box with a pair of leads feeding a box with 2 x 40amp mcbs for the electric showers - I have incorporated these in the new box (100 amp main switch, 15 way, split load, dual rcd protected 1 shower on each rcd) but when I work out total load I think its going to exceed the 63 amp max allowed for a 100 amp switch - is there any way round this?

3. the service fuse is 60amp - we have lived in the house for 3 months now without any problems but should I be thinking about getting the DNO to increase the fuse (they have told me 80 amp is the max I could get, subject to survey and a load of dosh!)

any help greatly appreciated!

andy

 

[ezzzekiel]

1. Extend cables with crimps in an accessible box
2. max demand diversity
3. 60a is pretty standard and will accomodate most domestic properties

 

[TPES]

General question to all (Dont see point in starting new thread)..

As your first question..
1. The cable ends I have are just long enough for the new CU ......

On a CU change you find the leg ends of majority of circuits are just long enough to reach the relivent bars (Earth & Neutral bars).. But not to go in the correct numbering sequence..

Would you not want any joins at all, just as long as you can get them in the correct bars..

Or

Crimp/join the ends out so they reach the correct number sequence

??

Ive heard different views from other sparks

 

[ezzzekiel]

although sequential is prefered then it is a matter of choice, if you wish to fit them where you can then a detailed notice of the sequence used is required.
if it was just one or two circuits i would be happy with this but if its most circuits then i would extend the cables

 

[andekoch]

incorrectly sequenced cables make future work a real pain for the next person so get it right now or carefully lable them so there can be no confusion in the future.

I agree with ezzzekiel in that for a few lables ok but if a lot then extend and get it right.

 

[rocker]

I'd extend every time - it looks like bum otherwise.

Why would you have to have the crimp (mechanical connection) (in heatshrink) in an accessible box though?

 

[ezzzekiel]

I'd extend every time - it looks like bum otherwise.

Why would you have to have the crimp (mechanical connection) (in heatshrink) in an accessible box though?

no reason, other than concealment i suppose (trunking would suffice) an access box used if din connected or similar and not crimped for future access