Existing REC & house supply

[cliffed]

just thoughts on this one.
Existing supply to barns from REC,300 amp Tncs 3p,cabling to House,fused of this via 100 amp cutout,by REC
Sub main 16 mm 2 core,to house.
Will the main bonding conductors be the size of the existing supply ie: 300 Amps regarding the neutral.

 

[buzzlightyear]

Iis this a idea or real .

 

[mhar]

If it is fed by a 2c submain cable then it will have to be tt if anything requires bonding.

 

[Wilko]

Hi - yes with PME - TNCS it's the incoming DNO neutral that sets the size of it.

 

[buzzlightyear]

Read guidance note 8 , cliffed .

 

[Deleted member 26818]

Are you sure the supply is TN-C-S?

 

[cliffed]

Cheers yea it’s tncs,agree TT,I done a EICR on it,been like it for years.

 

[cliffed]

Iis this a idea or real .

It’s real

 

[Deleted member 9648]

Is the 'submain' a private cable or DNO? If DNO they may be able to provide a TNCS connection at the load end if you enquire and you could then treat it as a 100a TNCS incomer..

 

[Deleted member 26818]

Is the 'submain' a private cable or DNO? If DNO they may be able to provide a TNCS connection at the load end if you enquire and you could then treat it as a 100a TNCS incomer..

It’s 2 core.

 

[Deleted member 9648]

It’s 2 core.

TNCS incoming cables normally are 2 core.

 

[Deleted member 26818]

TNCS incoming cables normally are 2 core.

2 core concentric, with the outer core being neutral and earth combined.

 

[Deleted member 9648]

The OP hasn't stated the cable type, only that it's 2 core.If it's DNO it will probably be concentric.

 

[cliffed]

It’s Swa cable not Rec concentric

 

[cliffed]

2 core concentric, with the outer core being neutral and earth combined.

No,it’s normal swa

 

[cliffed]

Is the 'submain' a private cable or DNO? If DNO they may be able to provide a TNCS connection at the load end if you enquire and you could then treat it as a 100a TNCS incomer..

Submain swa 2 core

 

[Wilko]

Hi - I think it's likely 25mm or 35mm would be needed (from Table 54.8). Not much help if it's all been installed and paved over, sorry ...

 

[cliffed]

Thanks,it frustrating,it’s been in forever,I’ve spotted it,but ain’t sure what’s gonna happen,most probably stay like it is