Drive over ground lights bonding question?

[scubadogct]

I am required to provide power to a shed, a pond (with pump) and some outside lights.
The lights are class 1 and are the drive over type.
The current earthing arrangement is PME.
This installation is in a garden with kids and animals present.

I have decided to install a CU in the shed and TT and spike it.
Reason being there will be plenty of Extreniuos conductive components from the pond and lighting.

I understand the need for the spike and the 16mm^2 bonding between the CU and the spike.
However looking at the osg its suggest a minimum 6mm bonding for water pipes ect.

The drive over lights, these are class 1 and will have extraneous condctive parts that are easily accesable by kids and dogs with wet feet ect. Will theese require the 6mm bonding as well?
They only have small 1mm terminals so i dont see how.
Tom be honest this is the first time i have installed lights that are easily touched...all of mine so far have been out of reach let alone actally in the floor.

 

[Clive P]

Hi,

Hmm, I think you should revisit the definition for extraneous conductive parts before we go any further, and welcome to the forum.

Regards.

 

[HappyHippyDad]

Hi Scuba,

Could you not extend the equipotential zone from the house by bringing the correct size 3 core SWA and using the 3rd core as the earth? Plus also bring a 10mm conductor for the bonding if required?

I'm not sure you would need the bonding cable if it is just the lights you are thinking about as I believe they would be classed as exposed conductive parts rather than extraneous and would be earthed by the supply cable that you bring to them.

 

[scubadogct]

Thanks for that..okay so i got my extraneous and exposed muddled up.
I had read the IET guidance note on electrical installations outdoors and hence why the mix of extreneous and exposed resulted in the decision to TT and spike.
With that cleared up i know understand i dont need to do that and can just extend the zone as mentioned earlier.
Thanks

 

[telectrix]

just make sure that all class 1 equipment is earthed. record your R1+R2 and Zs readings on the cert.