upgrade meter tails, or downgrade main incoming fuse??

[martinsayer81]

hi guys

hoping you could give me your thoughts,

i am pricing for a consumer unit change, its an old fuseboard with re-wireables.
it has 16mm meter tails, but it has a fairly new looking 100A main fuse.

its a small-ish house..... 2 ring mains, 2 lighting radials, a couple of sockets in the garage, and an immersion heater radial,

i was wondering whether or not i could just down-grade the main fuse to a 60A and keep the existing 16mm tails( no damage, or signs of overheating or burning)
or whether i have to leave the fuse at 100A and fit 25mm tails?

there's no electric shower or oven,

i would appreciate your advice

many thanks

 

[Octopus]

Are you sure its a 100A fuse in the holder.

I'd say leave the tails as is - but that's just my opinion

Tin hat on.

 

[telectrix]

as above^^^ it may say 100A on the outside, but be a 60A fuse on the inside. just leave the 16mm tails in, and the fuse is not your responsibility.

 

[MDJ]

Tin hat on.

:helmet: :44:

 

[jaydee81]

when you say 100 amp fuse do you mean dno supply fuse?

 

[Guest55]

the only way to know for sure is for your hand to slip onto the seal whilst holding snips...........

 

[SYKRAPS]

As #2 & #3 the 16mm tails were probably installed by the DNO along with the fuse, I would be more concerned that the earthing and bonding was correct for the supply characteristics

 

[martinsayer81]

its the dno 100A fuse,
at the moment i am just going on the sticker on the outside, it was late in the evening when i looked at the job, and couldnt pull the fuse to check,

wouldnt it be against the regs to leave the 16mm tails with a 100A fuse?

i just dont want to get any come backs

 

[Octopus]

its the dno 100A fuse,
at the moment i am just going on the sticker on the outside, it was late in the evening when i looked at the job, and couldnt pull the fuse to check,

wouldnt it be against the regs to leave the 16mm tails with a 100A fuse?

i just dont want to get any come backs

The OSG pictures assume you are working on a new build....

Do they have 3 electric showers, multiple cookers, a canabis factory in the loft..... The usage for a house is unlikely to rise about 35 amps so I'd leave them welll alone.

 

[143del]

Hold onto your snips martin,
The requirement for 25mm tails are part of the PME supply regulations so if the supply is PME there is no getting away from that

 

[jaydee81]

bet its only 16mm tails from dno cut out to meter anyway

 

[dim_bulb]

Is it a major hassle to upgrade? If not price it in you can get a 2 meter tail pack for 15 - 20 quid

 

[martinsayer81]

The OSG pictures assume you are working on a new build....

Do they have 3 electric showers, multiple cookers, a canabis factory in the loft..... The usage for a house is unlikely to rise about 35 amps so I'd leave them welll alone.

so, basically, if it does turn out to be a 100A fuse in the holder, it would still be ok to leave the 16mm tails due to a low demand?

 

[martinsayer81]

Is it a major hassle to upgrade? If not price it in you can get a 2 meter tail pack for 15 - 20 quid

is there any likelyhood of the meter breaking on me when i open it up to change the tails??

 

[martinsayer81]

its a tns supply, the only upgrade to the earthing i have to do is the main earth, all the main earth and earth bonding at the moment is 10mm

 

[GLENNSPARK]

Is it a major hassle to upgrade? If not price it in you can get a 2 meter tail pack for 15 - 20 quid

...i know where you can get a 3 meter 25mm tail pack for 3 quid......
well theres this bloke i know who works for the council.....he has a `clearout` once a month on the bootsale.....

 

[dim_bulb]

Yes but you didn't factor in the air fare it cost to go to china and back to get the gear

 

[GLENNSPARK]

Yes but you didn't factor in the air fare it cost to go to china and back to get the gear

what it is.....is their `offcuts`...their issued with...lets say a 25 meter drum of tails.....so they put more on a job..than it really was....the rest goes on the bootsale...lol....god, he`s got allsorts..C/Us chuffin RCBOs..drums of twin...lol...

 

[dim_bulb]

Sounds a good bargain, I'm only jokeing around
i only get gear at wholesalers as if there's a problem I feel I have a warranty in place

 

[143del]

OK Martin, With a TNS and a run of less than 2 mtrs you can use 16mm tails as a foot note they normaly fit 80 amp fuses in the DNO for domestic properties nowdays previously they fitted 60 amp

 

[SLSpark]

the main fuse may be 80-100amp i would upgrade the tails to 25mm the fuse is nothing to do with you but as you are upgrading the system why not upgrade the main tails as its fairly cheap to do so £10 max material , disconnecting them from old board anyway .
i always upgrade to 25mm tails and 16mm earth incoming

 

[Octopus]

the main fuse may be 80-100amp i would upgrade the tails to 25mm the fuse is nothing to do with you but as you are upgrading the system why not upgrade the main tails as its fairly cheap to do so £10 max material , disconnecting them from old board anyway .
i always upgrade to 25mm tails and 16mm earth incoming

So do you always cut the seals on the meter then?

 

[SLSpark]

consumers isolation switch is 30cm max from main fuse murdoch.

if there isnt a isolation point the electricity supplier will gladly fit this for £85 allowing the electrician to carry our his work without cutting seals or pulling fuse.

i could easily re seal using my sealing plyers and SP seals as i am authorised contractor

 

[Octopus]

consumers isolation switch is 30cm max from main fuse murdoch.

if there isnt a isolation point the electricity supplier will gladly fit this for £85 allowing the electrician to carry our his work without cutting seals or pulling fuse.

i could easily re seal using my sealing plyers and SP seals as i am authorised contractor

And all your customers are happy to pay this?

 

[SLSpark]

all my customers appreciate my good quality work,knowledge and professionalism so my advice is golden to them its not much of a hassle to have this done actually can benifit in future , they are there for a reason thats why every new build will have L in and out of switch and nuetral in & out

 

[Geoffsd]

I wonder what it will do to the copper prices if/when everyone has tails (and cables ?) 50% larger than necessary.

 

[SLSpark]

:s every new property has this as standard so copper prices are not the issue , the guys asked for advice put in 25mm and allow for growth of the electrical system

 

[Octopus]

:s every new property has this as standard so copper prices are not the issue , the guys asked for advice put in 25mm and allow for growth of the electrical system

Interestingly most products being bought now can be "greener" so when will the time come when we have to rip out 25mm tails and go around fitting 60A fuses!


LOL

 

[SLSpark]

this would never happen , i will leave you to carry on with your negative argumentative ways !!!!

 

[Octopus]

this would never happen , i will leave you to carry on with your negative argumentative ways !!!!

lol!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[Guest55]

murdoch needs a troll badge, you troublemaker you lol.

 

[SLSpark]

murdoch needs more than a troll badge ,guys obviously got issues and comes on here looking to see what post he can annoyingly comment on ,
SADDO

 

[dim_bulb]

murdoch needs a troll badge

Is that like a blue Peter badge? I want one

 

[SLSpark]

yeah basically annoying people who talk **** badge alot of guys on here should have gold plated ones

 

[Guest55]

yeah basically annoying people who talk **** badge alot of guys on here should have gold plated ones

calm down pal , its a forum , free speech , different views etc , etc.

 

[SLSpark]

yeah i agree its a forum ,free speech,etc etc sparks helping other sparks out with varieties of knowledge but some guys are just arrogant ,
the type of guys that sit there self at lunch , that no one likes

 

[Guest55]

Is that like a blue Peter badge? I want one

you'll need to be banned many times to get one

 

[Octopus]

murdoch needs more than a troll badge ,guys obviously got issues and comes on here looking to see what post he can annoyingly comment on ,
SADDO

For someone with only 52 post and no thanks I think you need to adapt your approach if you're to remain on this forum. Step over the line and the mods will throw you off.

- - - Updated - - -

murdoch needs a troll badge, you troublemaker you lol.

Troll badge - cool!

 

[GLENNSPARK]

For someone with only 52 post and no thanks I think you need to adapt your approach if you're to remain on this forum. Step over the line and the mods will throw you off.

- - - Updated - - -



Troll badge - cool!

can i taunt him for a bit murdoch......i can 100% guarentee that he wont be back after a taste of my argumentative skills....lol...

 

[Knobhead]

can i taunt him for a bit murdoch......i can 100% guarentee that he wont be back after a taste of my argumentative skills....lol...

Yes
What?
How many times Glenn?

 

[Knobhead]

all my customers appreciate my good quality work,knowledge and professionalism so my advice is golden to them its not much of a hassle to have this done actually can benifit in future , they are there for a reason thats why every new build will have L in and out of switch and nuetral in & out

Which planet are you on?

 

[MDJ]

:26: ah yes friday night again.

 

[Engineer54]

You only NEED 25mm tails is if there is a 100A cut out fuse. Otherwise 16mm will be fine!! It may be prudent to realise that a 100A cut out fuse can only be provided when the Ze/Zs available is adequate to provide clearance times....

I have yet to see a typical standard to large domestic installation come anywhere near drawing a 100A or anything close to it!! Far too many here take more notice of a guidance drawing in the OSG, than using their training and commonsense!!

 

[SLSpark]

Which planet are you on?

What u getting at ?
Customers don't call electricians in because they know what there talking about
Tony

 

[malcolmsanford]

Hold onto your snips martin,
The requirement for 25mm tails are part of the PME supply regulations so if the supply is PME there is no getting away from that

hmmmm.................................

 

[Knobhead]

:s every new property has this as standard so copper prices are not the issue , the guys asked for advice put in 25mm and allow for growth of the electrical system

Planet Spongle I think.

What groth of the electrical system, it's a house for gods sake!

 

[SLSpark]

Planet Spongle I think.

What groth of the electrical system, it's a house for gods sake!

Yes a house with no electric shower electric cooker ,pv system outbuilding supplys etc etc etc.

if the fuse is sealed and there is local isolation how do you know what size the fuse is ,only indication it the 100a sticker on cable head fuse.

still cant see the big fuss about fitting 25mm tails while changing a DB

:s

 

[SYKRAPS]

Its the weekend, everyone should be smiling and playing nicely

 

[imago]

Regulations, guidance notes, DNO requirements, actual demand figures, and fuse sizes. To be honest the main reason I upgrade to 25mm tails is for an easy/quiet life.

I could demonstrate by readings and/or calculations that 16mm would be more than adequate. The thing is though, it's easier, cheaper, and quicker just to swap the tails out, so I do. The same goes for 10mm to 16mm main earth and 6mm to 10mm bonding in a lot of cases too.

 

[SLSpark]

Regulations, guidance notes, DNO requirements, actual demand figures, and fuse sizes. To be honest the main reason I upgrade to 25mm tails is for an easy/quiet life.

I could demonstrate by readings and/or calculations that 16mm would be more than adequate. The thing is though, it's easier, cheaper, and quicker just to swap the tails out, so I do. The same goes for 10mm to 16mm main earth and 6mm to 10mm bonding in a lot of cases too.

my point exactly ,i also upgrade the main earth to 16mm,
no ones said 16mm mains tails isnt adequate but good practice to upgrade while changing DB.