Tncs and tt

[LVSparks]

Was at a job today and noticed at the main incomer, it was an underground fed 2 core swa I think supplied by the leccy board. It had the neutral link up to the meter but didnt have the main protective bonding conductor from the same neutral tap off over to the met. Instead a pe went outside to a rod from the met, creating a tt.
Im pretty sure this is incorrect but would love to hear from some technical sparks on this situation please.
Just to add the rod was completely exposed and the installation was not protected by rcds as requried if a tt system. It cleary looks as if it was designed to be a tncs system.

 

[Marvo]

I don't think I'm fully understanding the arrangement, can you post a picture or two?

 

[Knobhead]

SWA? I’d check that before you make a total arse of yourself with the DNO.

 

[LVSparks]

SWA? I’d check that before you make a total arse of yourself with the DNO.

Forgive me it was late when I wrote this post, its not swa its a 2 core fed in metal conduit fed from underground. Supplied by dno and has the head set up for a tncs system.

 

[telectrix]

metal conduit or lead sheath?

 

[tony mc]

Just because the head set up is for TNC-S does not mean it is . Do some testing and make some enquiry's !

 

[LVSparks]

metal conduit or lead sheath?

Definitely metal conduit and not tn-s

 

[Outspoken]

If it is a 2 core coming in via a conduit then you have answered your own question.

 

[Knobhead]

I’ve known a DNO supply to be VIR in 1” conduit but that was 50 years back. It was on my grandfather’s farm, god alone knows when it was installed.

The conduit was rotten and falling apart. The OH supply was terminated at the end of the house and then run in the conduit for about 20 yards to the meter. The only earth was the water pipe.