Meter tails at 25mm!

[Resu]

CSA is cross sectional area (not including sheath), what you have measured is the diameter including the sheath. Looking at those pictures I would put money on those being 25mm.

For example if you cut one of the tails and looked at it end on you would be looking at an area or 25mm2 of copper.

 

[Leesparkykent]

Trying to tell by the ruler but it looks slightly over 10mm? More like 11mm

 

[Resu]

And to add:

Point 3: you will not get a 25mm tail into a domestic boards's neutral bar.

Point 4: a domestic board incorporates a 100A double pole switch (the main switch). These will easily take 25mm tails.

 

[Carlos Arruda]

How can a level 3 trainee not know the difference between cross sectional area and outside diameter ?

Andy,

I must have been sleeping throughout the whole three years.

Being a father of 2 toddlers and holding a full time job, is a huge commitment as some well know.

I get what you are saying, but until now, and thanks to your comment, an eye opener, that I realize the error of my way.

I guess when one looks at a cable that looks like 1.0mm and 2.5mm (CSA) the assumption was there that these were in fact 1.0mm and 2.5mm thick.

Many thanks.

Regards,
Albert

 

[Carlos Arruda]

Trying to tell by the ruler but it looks slightly over 10mm? More like 11mm

You are correct.

So what would one say the cable itself is? 9.0mm? If removing the sheathing!

 

[Carlos Arruda]

Multi core cable refer to where there is more than one conductor enclosed in a sheath, so cables such as T&E, SWA etc

I got it mixed up with stranded cable mate, sorry.

 

[Leesparkykent]

You are correct.
So what would one say the cable itself is? 9.0mm? If removing the sheathing!

Nominal Overall Diameter of 16mm double insulated tails is roughly 9.75mm

Nominal Overall Diameter of 25mm double insulated tails is roughly 11.5mm

 

[Carlos Arruda]

Apologies to all for the CSA / diameter confusion.

I am utterly letting myself down and my tutors also.

Pretty sure this was mentioned in the class at some point.

I just got so used to thinking 1.0mm, 1.5mm and 2.5mm CSA as being it's width, that lead to all this confusion.

Many thanks to all that offered their comments, views and/or opinions.

Always learning.

I fell that the changing of ideas here on the forum, the typing of all the materials, sources of info and regulations is priceless and helps so much more. Undoubtedly a great addition of information to add to that of the classroom.

Thanks everybody.

Apologies if I was in any way a tad out of order.

Regards,
Albert

 

[Leesparkykent]

Apologies to all for the CSA / diameter confusion.

I am utterly letting myself down and my tutors also.

Pretty sure this was mentioned in the class at some point.

I just got so used to thinking 1.0mm, 1.5mm and 2.5mm CSA as being it's width, that lead to all this confusion.

Many thanks to all that offered their comments, views and/or opinions.

Always learning.

I fell that the changing of ideas here on the forum, the typing of all the materials, sources of info and regulations is priceless and helps so much more. Undoubtedly a great addition of information to add to that of the classroom.

Thanks everybody.

Apologies if I was in any way a tad out of order.

Regards,
Albert

Not at all mate, every day is a school day.

 

[Carlos Arruda]

Would it be normal practice, on a TN-C-S system, to see 3 CPC cables coming out of the DNO side?

The cables in question look like 4.0mm (CSA) stranded.

Why not use one cable of a greater CSA?


P.S: Please note this is not in relation to the pictures posted. I have seen this on a friends house who want's their C.U. changed. I have mentioned this change on another post.

 

[Leesparkykent]

Would it be normal practice, on a TN-C-S system, to see 3 CPC cables coming out of the DNO side?

The cables in question look like 4.0mm (CSA) stranded.

Why not use one cable of a greater CSA?


P.S: Please note this is not in relation to the pictures posted. I have seen this on a friends house who want's their C.U. changed. I have mentioned this change on another post.

Main earthing conductor, bonding to gas and bonding to water? Albeit undersized.

 

[Carlos Arruda]

Main earthing conductor, bonding to gas and bonding to water? Albeit undersized.

I was under the impression that the main bonding (to water and gas) would be provided by the consumer unit.

No gas in the house, only water.

 

[Leesparkykent]

I was under the impression that the main bonding (to water and gas) would be provided by the consumer unit.

No gas in the house, only water.

Can you work out where they go?

 

[Carlos Arruda]

Can you work out where they go?

From pics I've taken, it looks like two of these are at the old rewirable fuse board which makes the 3rd cable likely to be on the water intake.

 

[Barry White]

looks like you are measuring the outer diameter to get 10mm 25mm is the cross sectional area
6181Y tails
16 mm = 9mmouter diameter
25mm = 11mm outer diameter

silly me didnt see page 2 Doh

 

[davesparks]

It was normal practice in years gone by for the bonds and earthing conductor to all be 6mm and connect in to the earthing terminal of the cutout. It's almost always the black henley cutout with the little removable cover over the earth terminal which pokes out of the right hand side.

 

[Carlos Arruda]

looks like you are measuring the outer diameter to get 10mm 25mm is the cross sectional area
6181Y tails
16 mm = 9mmouter diameter
25mm = 11mm outer diameter

Absolutely mykey.

Made myself look a real plonker...

 

[Carlos Arruda]

It was normal practice in years gone by for the bonds and earthing conductor to all be 6mm and connect in to the earthing terminal of the cutout. It's almost always the black henley cutout with the little removable cover over the earth terminal which pokes out of the right hand side.

You are dead on the money davesparks.

P.S: I suppose electrician are to refrain from touching this and replace it given it's in the DNO side?

 

[Darkwood]

Carlos ... you been a Trainee would be better asking these questions in the Trainee section, not everyone will note your a Trainee in the main forum before answering and can lead to off putting replies.

Their are no regulations stating the size of the tails, as has already been mentioned your tails are designed for the upfront fuse in this case and as we usually don't have access to the DNO fuses we must assume in domestic it may have a 100amp fitted.

Tails can utilise another regulation where the actually demand on them is restricted by the load they supply so say you had a 1way board for a shower then your tails could be say 10mm because the 40amp - 50amp rated fuse for said shower would ensure the demand on the tails could not exceed its CCC. This is limited to cables < or = to 3m.

So it is just the norm to fit 25mm tails on larger multi-way boards when the DNO fuse carrier is 100amp regardless of the rating of the fuse inside which we normally cannot access.


As for schoolboy errors ... don't worry about it we all did and some still do them, jeez I just found out its brown that's the Live one now that's 25yrs of plug tops I need to rewire.:sick:

 

[Carlos Arruda]

Carlos ... you been a Trainee would be better asking these questions in the Trainee section, not everyone will note your a Trainee in the main forum before answering and can lead to off putting replies.

Their are no regulations stating the size of the tails, as has already been mentioned your tails are designed for the upfront fuse in this case and as we usually don't have access to the DNO fuses we must assume in domestic it may have a 100amp fitted.

Tails can utilise another regulation where the actually demand on them is restricted by the load they supply so say you had a 1way board for a shower then your tails could be say 10mm because the 40amp - 50amp rated fuse for said shower would ensure the demand on the tails could not exceed its CCC. This is limited to cables < or = to 3m.

So it is just the norm to fit 25mm tails on larger multi-way boards when the DNO fuse carrier is 100amp regardless of the rating of the fuse inside which we normally cannot access.


As for schoolboy errors ... don't worry about it we all did and some still do them, jeez I just found out it brown thats the Live one now that's 25yrs of plug tops I need to rewire.:sick:

Darkwood;

Many thanks for he input and suggestion.

I have applied to join the trainee only forum but haven't yet got a reply.

Or I might be missing something.