maxium lengh of meter tails ??

[perfect1000k]

hi there what is the maxium lengh of meter tails you can use is there anywere in the regs it states what it is any help would be great cheers

 

[yellowvanman]

Generally DNO specifies that distance from meter to Consumer unit should be no more than 3 meters.

If you want to run further then you need a Switched Fused, from there you could run in any suitable cable. I've seen a run of over 30meters in tails protected by a 63A MCB/RCD - OK as long as the tails have 2 layers (like T&E) of protection - insulation & outer sheath.

 

[Noton1205]

From cutout to ccu should be no more than 3 meters unless you install a switchfuse before the ccu.

 

[malcolmsanford]

As yellowvanman says it is dependant on the DNO, and the rule of thumb is 3-5 metres. It will though be dependant on the Ze of the external system as that will govern the PFC of the DNO protection device.

The DNO will not guarantee anything really over 5 metres, so you can go for err on the side of caution and us the 3metres rule. or take the Ze and contact the DNO engineering department and ask for guidance.

 

[Noton1205]

I know british gas and uk power netwroks in the south east will use 3m from the cutout to the ccu, meter in between.

 

[sparks1234]

From cutout to ccu should be no more than 3 meters unless you install a switchfuse before the ccu.

Can I just clarify that the switch fuse goes within the first 3 mtrs, not just before the CCU, some one may read that and misinterprete

 

[Noton1205]

Sorry sparks1234 is correct, i did mean that its 3m from cut out to ccu or cut out to switch fuse.

 

[perfect1000k]

thanks for the replys lads looks like i owe someone a bacon on toast in the morning lol

also why have i seen tails 25mm running from outside meter box (white one on side of house ) running into the cavity across the loft down into the airing cubord (bungalow) about 15 meters in all ?

seen this on a few council houses ive worked on in past 6-7 months

 

[Noton1205]

Sounds abit like the person doing these ownes a horse.

 

[mattmoo1974]

Get off your horse and drink your milk pilgrim!

 

[malcolmsanford]

thanks for the replys lads looks like i owe someone a bacon on toast in the morning lol

also why have i seen tails 25mm running from outside meter box (white one on side of house ) running into the cavity across the loft down into the airing cubord (bungalow) about 15 meters in all ?

seen this on a few council houses ive worked on in past 6-7 months

Perhaps they had the DNO permission to do this. As I said it is their rules on length of tails as it is there protection device that cover PFC.