25mm tails why..?

[Dustydazzler]

Have you ever come across a melted 16mm tail ? Me , no never ...

why are tails expected to be 25mm , seems utter overkill imo

thoughts

 

[Ian1981]

Yes I agree however it goes against the regs by using 16mm tails on 80A/100A fuse

No it doesn’t

 

[LastManOnline]

if I had my way 16mm tails we be the norm for all domestic property.

25mm is total overkill imo...

Agreed on overkill comment. On the positive side there is no question that UK consumers are absolutely futureproofed with a 25mm supply. You do wonder at times though about cable current ratings in general when a 6mm is deemed adequate for a 40 amp mcb (all other factors permitting) but a 25 mm is required for an 80 amp fuse.

 

[Ian1981]

Agreed on overkill comment. On the positive side there is no question that UK consumers are absolutely futureproofed with a 25mm supply. You do wonder at times though about cable current ratings in general when a 6mm is deemed adequate for a 40 amp mcb (all other factors permitting) but a 25 mm is required for an 80 amp fuse.

Nothing wrong with 16mm tails clipped direct on a 80 amp fuse.
Nothing wrong with 16mm tails on a 100amp fuse if they’ve been there for years without suffering thermal damage and the loading of the installation does not exceed the ccc and they have adequate fault protection.

 

[LastManOnline]

Nothing wrong with 16mm tails in free air or clipped direct on a 80 amp fuse.

That's good to know. I was under the impression that 25mm was your standard DNO supply in UK. Am I correct in assuming that the 25mm is required for a 100 amp supply?

 

[Ian1981]

That's good to know. I was under the impression that 25mm was your standard DNO supply in UK. Am I correct in assuming that the 25mm is required for a 100 amp supply?

New supplies like new build housing up my way , the dno stipulate 25mm tails and a 16mm earthing conductor with a 100 amp main fuse.

 

[Paul Maughan]

What’s the actual actual cost difference on a couple of meters of meter tails ? £5 ? I just whack 25mm in every time and worry about other things ?

 

[Ian1981]

I think the 16mm tails is more if they are already in situ and replacing them would be awkward and costly to the client when it doesn’t need to be and don’t need replacement ie meter tails 15 meters away and installed within the fabric of the building.

 

[telectrix]

What’s the actual actual cost difference on a couple of meters of meter tails ? £5 ? I just whack 25mm in every time and worry about other things ?

what about the cost in arthritis in the joints from bending and threading 25mm into a poxy CU with ahrdly any room ?

 

[Ian1981]

what about the cost in arthritis in the joints from bending and threading 25mm into a poxy CU with ahrdly any room ?

Flexi tails are a game changer, bendy bendy.

 

[Paul Maughan]

what about the cost in arthritis in the joints from bending and threading 25mm into a poxy CU with ahrdly any room ?

We’re all ----ed anyway ?

 

[telectrix]

i have to say that though i am plagued with several aches and pains, none is arthritic as yet. still, only 73, so plenty of time yet . till then i'll carry on installing until such time as i can no longer cope, or 80, whichever comes first.

 

[stevethesparks]

Just as a side note, I'd like to see any bottom tails entry that conforms to the bending radius guidelines.

 

[LastManOnline]

i have to say that though i am plagued with several aches and pains, none is arthritic as yet. still, only 73, so plenty of time yet . till then i'll carry on installing until such time as i can no longer cope, or 80, whichever comes first.

Good on ye?

 

[Dustydazzler]

G

i have to say that though i am plagued with several aches and pains, none is arthritic as yet. still, only 73, so plenty of time yet . till then i'll carry on installing until such time as i can no longer cope, or 80, whichever comes first.

good on you Tel , my dad managed to keep working till he was about the same age but unfortunately suffered a mini stroke which messed up his right hand which ment he literally couldn’t hold anything without dropping it...
he would have carried on as loved his work but just couldn’t...

 

[Grant1987]

the physical lenghth of most meter tails is abit 1m-1.5m

to melt a 16mm csa cable of that length I reckon you would have to run 300-400a through it

Yes you’re right and I’m constantly coding C3 for undersized meter tails. Just out of curiosity what do you code 6mm twin and earth with 10/15 mtr run to shower with power consumption of 9kw with thermal effects at pullcord? (Melted)