TNS or TNCS odd installation

Richard Gliddon · Jan 21, 2019

Came across an odd supply in my sisters house

Looks like an earth link from the outer for TNS but a also earth terminal as if it were TNCS?

[ElectriciansForums.net] TNS or TNCS odd installation

Deleted member 26818 · Jan 21, 2019

I would say TN-C-S.

Nigel · Jan 21, 2019

I would say a TN-S with a dodge link put to the neutral by someone that thinks they know what they are doing.

I would call the DNO to confirm. I would guess the TN-S was poor so someone has just bridged the neutral to earth to get the Ze down but the DNO would not do it like that.

The DNO may well just link it but PME may not be available so they may remove the link altogether.

Glen Handley · Jan 21, 2019

This is a PME TNCS as I had a TT at a customers house the other day and requested a PME and they came and did the same thing ie made connection onto the outer sheath and then linked it via a henley to the neutral/ earth on the cut out.

buzzlightyear · Jan 21, 2019

TN-S system, final answer, the DNO kept that way so they dont loose the earth back from sub station .

Silly Sausage · Jan 21, 2019

Glen Handley said:
This is a PME TNCS as I had a TT at a customers house the other day and requested a PME and they came and did the same thing ie made connection onto the outer sheath and then linked it via a henley to the neutral/ earth on the cut out.

You can see the seal on the Neutral block cover.

buzzlightyear · Jan 21, 2019

Archy Styrigg said:
You can see the seal on the Neutral block cover

why would the DNO do that ,I would confirm with DNO .

Andy78 · Jan 21, 2019

This is how Northern powergrid connect new heads onto existing cables when I request a cast head removed. I have seen them do it quite a few times now and it is always a TN-C-S connection when done by them. They link neutral earth at the head to the sheath earth. "It's just how we do 'em now" is the general answer to my question of why.