Regulations concerning meter tails

[DaveS79]

Evening all

Can someone point me to any specific regs that deal with protection of meter tails. I.e when double insulated required? Or what other protection may be adequate. Was on job the other day and meter located outside property with a run to consumer unit of about 2.5 meters in non insulated tails. I couldn't see any sort of mechanical protection that was provided for these. I have also seen non insulated tails run to consumer unit in a flexible conduit I would just like to clarify exactly what the regs say that are classed as adequate protection for these. Thanks

 

[Evans Electric]

They require mechanical protection  , as does any exposed wiring .    

What has been installed ?   Single  insulated 6491X     instead of 6181Y     Insul/sh'd  meter tails .? 

 

[Jono Pashley]

Single insulated must be in containment and may require de-rating. Specific regs? come on youre supposed to be an electrician why dont you start in chapter 4

 

[DaveS79]

They require mechanical protection  , as does any exposed wiring .    

What has been installed ?   Single  insulated 6491X     instead of 6181Y     Insul/sh'd  meter tails .? 

6491X Andy and is in flexible copex. If the tails are run within voids greater than 50mm and/or within safe zones does this ommit the need for double insulation or additional protection via RCD? If neither present and tails run within 50mm of surface the plastic copex surely isn't classed as providing mechanical protection is it?

 

[Sharpend]

It just sounds a poor installed job, how difficult is it to come by double insulated tails ? 

 

[Murdoch]

What are planning to do on this site?

 

[DaveS79]

It just sounds a poor installed job, how difficult is it to come by double insulated tails ? 

What are planning to do on this site?

I'm just doing some rewiring on his kitchen but has asked me to quote on new fuseboard. Got concerns though them tails aren't going to be easy to wire through the copex. Interested to know if this proves to be a mare is there possibilty existing tails could be deemed adequate.

 

[Murdoch]

I'm just doing some rewiring on his kitchen but has asked me to quote on new fuseboard. Got concerns though them tails aren't going to be easy to wire through the copex. Interested to know if this proves to be a mare is there possibility existing tails could be deemed adequate.

All you can do is quote for the job and see it he wants it done .

 

[Sharpend]

This 2.5 meter run, where is it straight up, up and across? In the brick/block void? 

 

[DaveS79]

This 2.5 meter run, where is it straight up, up and across? In the brick/block void? 

The meters sat within plasterboard in landlord area. The copex running straight up so depending on how tight bend is could be bit of a tight pull. Just for clarity the only reason these tails would need to be upgraded to double insulated would be if run within 50mm of surface and either not mechanically protected or protected with rcd?

 

[Sharpend]

Which bend? 
 

if the tails are going straight up then they can usually be fished up the void and brought out where the cu is positioned, obviously with Cu removed for ease. Don’t tell building control they are in the void as they get all het up over bridging the void causing damp issues etc. Be aware of any insulation in the void, if it’s the polystyrene balls they are a nightmare, best to plug void with a piece of card whilst fishing cables otherwise most of insulation ends up on the floor, which is good for cable derating values but not so good for heat loss from building! S’pose can’t have it all ways!?

 

[DaveS79]

Which bend? 
 

if the tails are going straight up then they can usually be fished up the void and brought out where the cu is positioned, obviously with Cu removed for ease. Don’t tell building control they are in the void as they get all het up over bridging the void causing damp issues etc. Be aware of any insulation in the void, if it’s the polystyrene balls they are a nightmare, best to plug void with a piece of card whilst fishing cables otherwise most of insulation ends up on the floor, which is good for cable derating values but not so good for heat loss from building! S’pose can’t have it all ways!?

Nice one mate. The copex runs up and then to left to a about a meter into flat. If can't get new tails through existing copex sure I'll find a way of fishing them through once I get fuseboard off. Might be pain but where there's a will there's a way

 

[Sharpend]

You may find that there is a significant hole behind the cu already from original pull in. Usually some flexible rods either up from outside (generally easier) or down from inside. I used to use a piece of blue water pipe on site most handy as had a natural curve for going around meter box dpc. Well actually thinking about it you could tie on to existing and use them as a pull through. 

 

[DaveS79]

You may find that there is a significant hole behind the cu already from original pull in. Usually some flexible rods either up from outside (generally easier) or down from inside. I used to use a piece of blue water pipe on site most handy as had a natural curve for going around meter box dpc. Well actually thinking about it you could tie on to existing and use them as a pull through. 

yeah hoping existing will make life easier. Got concerns though tails might be undersized, gotta have proper check when go back....life of a spark hey different day different problem to sort

 

[Sharpend]

That’s what makes it so interesting! 

 

[Murdoch]

yeah hoping existing will make life easier. Got concerns though tails might be undersized, gotta have proper check when go back....life of a spark hey different day different problem to sort

you’ve mentioned the landlords area - are these tails protected by a switched fuse? 
 

just because they aren’t 25 mm doesn’t mean they need to be. The pretty picture in the OSG is misleading

 

[DaveS79]

That’s what makes it so interesting! 

Haha it does mate

you’ve mentioned the landlords area - are these tails protected by a switched fuse? 
 

just because they aren’t 25 mm doesn’t mean they need to be. The pretty picture in the OSG is misleading

They are Murdoch. It's rated at 100amps though. I'm aware I may still be able to get away with this? If max demand of install won't exceed CCC of 16mm's but haven't had chance to check this and not a pro where diversity concerned so think best to quote on basis might need to change tails. 

 

[Sharpend]

What is in the landlords supply? 

 

[Phoenix]

Am I missing something here? If these are 6491x singles in kopex between switchfuse and consumer unit, then what is the problem?

 

[DaveS79]

Am I missing something here? If these are 6491x singles in kopex between switchfuse and consumer unit, then what is the problem?

Not at a depth of 50mm and plastic copex not classed as mechanical protection?