16mm t+e sub main

[wac]

hi i need sum info on using 16mm twin + earth as a sub main iam running it to a flat abt 25meters in a 1 foot floor void from a 63A/80A mains isolator next to main supply do i need to pull in a bigger earth cable in and if so wot size id look it up in regs book but had it stolen

 

[green-hornet]

If I supply a 16mm t&e from a mains to a DB I normally run a seperate 16mm earth as well.

 

[steptoe]

If I supply a 16mm t&e from a mains to a DB I normally run a seperate 16mm earth as well.

10mm earth as a minimum I would think.

what size of protective device, and whats the cable length?

oh, and whats the supply type?

 

[wac]

its abt 30meters comming 60A/80A fed from a 100A main supply not sure if its a tncs mains not in yet

 

[Sidewinder]

will almost certainly be TN-C-S unless you TT.

Almost all DNO supplies these days are TN-C-S/PME.

p.s. Just don't tell Steps......



Paul

O)

ROTFWL ROTFWL ROTFWL ROTFWL

 

[PC Electrics]

Presumably as you posted a repeat post at 22:19 (which Admin sensibly deleted), you did not realise that your question has been answered, above.

Basically, if you are using t&e and there are services in the flat which require MPB, then you will need to pull in a 10mm g/y also. In this case why not just use swa and just pull in one cable (or if the flexibility is needed use 16mm 3c H07RN-F).

Presumably this distribution circuit is not going to be buried <50mm in any walls?

 

[PC Electrics]

Yes, Sides. That's my presumption.

 

[steptoe]

will almost certainly be TN-C-S unless you TT.Almost all DNO supplies these days are TN-C-S/PME.

p.s. Just don't tell Steps......



Paul

O)

ROTFWL ROTFWL ROTFWL ROTFWL

this is PME , anything else is just TNCS

if its not labelled as such then IMHO its not.

 

[M107]

Pull in a seperate 16mm earth or as PC~ say's go 3c swa at 16mm

 

[wac]

so how wud u go abt it 10mm or 16mm earth????headbangheadbangheadbang

 

[steptoe]

as an aside,

16mm on an 80A protection......

have you calc'ed it to see if 16mm is OK.?

 

[PC Electrics]

so how wud u go abt it 10mm or 16mm earth????headbangheadbangheadbang

You need to pull in a size to suit the needs of the MPB. 10mm minimum, but the size is dictated by the supply characteristics (table 54.8).

 

[ElectekAir]

My question is who would want to steal a regs book???

 

[m4tty]

[No message]

 

[binky]

Have just done something similar and pulled in 16mm earth as well especially as its on TN-C-S, you're rubbing off on me Steps:^O.

Might I suggest 16mm spilt concentric cable - same as DNOs use, smaller and easier to handle the FTE or SWA, and comes complete with 16mm earth built in. Did this on a job some years ago where I had to run outside the building and come back in to flat to avoid other properties and damage to decor etc on a 40m run. Went in a doddle.

 

[PC Electrics]

Split con is a good idea. Easier to use than SWA and probably cheaper than the H07 I suggested.

 

[steptoe]

Have just done something similar and pulled in 16mm earth as well especially as its on TN-C-S, you're rubbing off on me Steps :^O .Might I suggest 16mm spilt concentric cable - same as DNOs use, smaller and easier to handle the FTE or SWA, and comes complete with 16mm earth built in. Did this on a job some years ago where I had to run outside the building and come back in to flat to avoid other properties and damage to decor etc on a 40m run. Went in a doddle.

its NOT me,

its that stoopid system called TNCS

in fact it wouldnt matter what they called it, ST_OO_PI_D would be the best name IMHO. LOL

good job most of the usual on here have learnt that Im a twisted cantankerous git.!