Existing Tails

[sparky1502]

I wonder how many of us change the tails from 16 to 25mm2 when we do an upgrade. We only know limited info on the property. To the op as long as the rated cut out fuse is 80 amp or 60 I would change the cu and leave the 16mm2 tails in and hand you an installation certificate

 

[Octopus]

tin hat on. 16mm tails, no electric heating, no electric shower, no electric cooking = leave tails as is.


Tin hat on!

 

[Silly Sausage]

I swapped my 25mm tails for bare naked 4 mils, keeps the hallway warm.

 

[somersetsparks]

I would change tails if easy, leave them if a b***rd and no signs of heat damage, regardless of fuse size

 

[telectrix]

I would change tails if easy, leave them if a b***rd and no signs of heat damage, regardless of fuse size

totally agree. i've had 16mm running at 110A and measured the temp. after 30mins. guess what 40deg.C. only slightly warm.

 

[Geoffsd]

Table 4D1A

 

[Silly Sausage]

Is there an equation or something to work out how hot a cable is with a certain current flowing through it?

 

[JoeDurky]

I've always changed tails just the way I was taught. It's easier and neater to work with new tails IMO. Dress them in nicely and leave slack for re-termination. As I said my opinion not everybody's and I completely understand why others wouldn't

 

[somersetsparks]

totally agree. i've had 16mm running at 110A and measured the temp. after 30mins. guess what 40deg.C. only slightly warm.

A certain DNO round our way (not us) only ever fit 16mm tails to their meters it seems, we are told not to bother unless heat damaged etc when changing meter, 16mm is adequate for any average sized gaff IMO

 

[Engineer54]

Thanks all your replys guys i am still confused though.... my fuse box is old wire fuses.
At first i am told new Cu
then i am told must have more expensive rcbo's to comply fully with regs
then i am told existing wire to meter is not 25mm but ony 16mm and needs replacing
and tails out are not 25mm but only 16mm and need replacing to comply fully with regulations.

So my question is this..... can a qualified electrician with part p change only the CU and get a certificte

thanks again guys

I think you have had more than enough good advice on the replacement of your CU and incoming tails for you to make an educated decision on what is and what isn't required. It's now up to you what your going to do!!

 

[ic3y]

I doubt it will cost much anyhow, look we all know it isn't a requirement, but FFS, the guy is having a new DB, a brand new kitchen which costs thousands and he's flucking worried about a couple of 25mm2 tails, unreal, get on with it man, get 2 or 3 quotes for a db change, don't even mention the tails, any spark with a brain and any intelligence will do whats required without itemising this item, and why are you worried about it, it's an easy Job, if it is that hard to install 25mm2 tails then chop the pipe out haha, the spark doing the DB has to certify it and if you don't let him change the tails (even though they may not need to be done) he may refuse to change the DB and the kitchen won't get fitted.

I don't think i mentioned cost! although if you must know it is coming in over budget.

I was trying to find out regulations, time was the issue as a straight cu change is done in a day.
as i now will have to wait for the electricity board to come and change incoming supple wires to 25mm... and do a lot of other work to get supply the house.

 

[Octopus]

I don't think i mentioned cost! although if you must know it is coming in over budget.

I was trying to find out regulations, time was the issue as a straight cu change is done in a day.
as i now will have to wait for the electricity board to come and change incoming supple wires to 25mm... and do a lot of other work to get supply the house.

I must confess you are still confusing me.

 

[ic3y]

I think you have had more than enough good advice on the replacement of your CU and incoming tails for you to make an educated decision on what is and what isn't required. It's now up to you what your going to do!!

I dont want to make an educated decision i want to know what is legal! lol

 

[ic3y]

I must confess you are still confusing me.

I have been told by electrician incoming supply needs changing to 25mm (electricity board job) tails need changing to 25mm new cu with rcbo's is needed acording to regulations. I am just trying to find out what is legal this job has gone from a day to taking weeks...

i was originally told it was only a CU changed..........still confused?

 

[MDJ]

question? if you decide to keep the 16mm2 tails how are you going to isolate them so the DB is dead for replacement?