I assume its the box that covers the rod with the "safety electrical connection, do not disconnect" label on top of it??

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Nope its all of them - all the excellent pictures of Lecs are various type of earth rod pit box and all must be suitably labelled.

Welcome back Keith.

Actually it has little to do with using welders or the like, well not really.

The issues are that-

(A) The regulations specify that the voltage drop between your house and the shed must be within a specified limit governed by several factors. True the maximum loading has something to do with this but there are other factors as well. The distance from source (house) to shed) has a lot to do with it. Also the type of installation mainly of the cable and the cable type. This was why we rattled on about using SWA, XPLE and NOT using twin-and-earth (T/E)

B) The earthing type we were all talking about (TN-S, TNC-S/PME and TT) are the main common types used by DNO (the people that supply your house, not the people  to whom you pay your bills necessarily).

TN-S (Terra, Neutral, Separated) means just that - that the earth to your house is separated from the neutral. That is the cable coming into your house has the live, the neutral AND the earth conductors. I think i is one of the safest systems  others may differ in their opinion and I would export the earth to your shed.

TT (Terra-Terra) means that the supplier does NOT provide you with an earth. Somewhere in your grounds will be an earth rod. I would not export this by definition and would install a rod at the shed.

TNC-S (Terra, Neutral, Combined and Separated) is where the neutral coming into the house is at earth, the supplier has earthed the neutral many times on its way to your house. Hence it is sometimes called PME (Protective Multiple Earth). I would never export this earth for the reasons that Lec enlightens to above (in case of a neutral fault condition the 'earth' could raise to 230 volts!!)

I suggest that you get a sparky in just ask his/her advice before you start, it is with a couple of pints as a tip! The fact that what you are proposing to do comes under the building regulations is another matter altogether  

Best of Luck and don't do anything risky your wife and kids need you. OK.

Pleasure Keith. Steady as it goes though don't want YOU being the only path to earth  

So ding, a wooden shed with a socket in it.....are YOU and Chubbs happy with TN-C-S?

Whats wrong with a wooden shed with a socket in it on tn-c-s? (i have read and understood this topic by the way). If its rcd protected should it not matter, (and i dont mean that in the sense that if something is rcd protected then what the heck). Can the line and earth carry voltage at the same time if you lost the neutral, without tripping the rcd protecting the shed?

Sorry if this reply seems stupid

Yeah i understand that rabbit, just thought being rcd protected etc... but yes, no harm in eebads. Shed is wood also, so nothing to touch that could become live, unless the socket or other piece of electrical accessory is class 1 i suppose. There is always a need to worry as far as electrics go tho, doesnt hurt to be more carefull!

I gotta question that hasnt been answered yet, on the new test certs there is a rectangular box which states next to it "method of protection against fault protection" Should RCD now be entered, EEBADS or both?

thanx

It's now Automatic Disconnection of Supply or ADS. At least that's what it says in the NICEIC BS7671:2008 17th Edition Learning Guide.

is that the 17th learning guide they give you wen u take the 17th update course? I got that off someone at work to look at, got my 17th update next month, been told its easy but im reading the guide just in case!

And to rabbit, i didnt think of the shed being wet on a rainy day/night! See, you can never be too carefull