Identifying Earthing System

[catdog]

Maybe an obvious one for some.... but would i be right in thinking this is TNCS??

Thanks guys.

 

[Leesparkykent]

More than likely TNS rather than TNCS

Put your MFT onit and measure PEFC and PSCC if they are the same then it’s TNCS if they are different then it’s TNS. I would almost guarantee it’s TNS though.

 

[Richard Burns]

I would agree, despite the initial appearance, it would likely be TNS.
However the arrangement seems odd, it would appear to be a split concentric cable, which would mean that this has been installed separately from the incoming supply as a supply cable would not be split concentric unless it is coming direct from a local transformer.

 

[Yplan]

I would echo what the fellas above had said at first glance it looks tncs but I would say tns.

 

[catdog]

Thanks for advice guys.

Yeah I'm not great on supply side of things for times like this- also never actually worked with split concentric but was assuming that's what it was.

Obvs for a single phase usually quite easy to spot a TNS.

Also the installation is a commercial unit of steel construction-does anyone know the reason the supply authority picks the earthing system for supplies?......or does it just depend on the type of cable lying nearby?.........or even the weather that day....?

 

[mhar]

The dnos work under ESQCR regs so not to BS7671.
For routine connections a system/network planner will be the person who decides what the network can support with regard to the proposed installation. Above him/her is a network technician. Higher up the ladder is the Protection Specialist who is god-like within the organisation