Earth Electrode Concern.

Catch hold of it and give it a yank to see it it comes out of the ground or has actually rotted off just under the surface.


I have condemned several because they have failed that test, all that remained of one rod was about six inches. If it passes the being yanked out of the ground test hook your loop tester up to it and see what that says.


Andy B.

Galvanised rods are common in some areas - I've a feeling that the Irish regs prefer them over the copper clad ones we usually use (I think there was a suggestion that they lasted better in the typically peaty acidic Irish soil). There's a risk the protective coating could have been damaged during driving (but presumably there would be some of that risk with copper clad rods too). So I'm with Andy - if if checks out physically & electrically I wouldn't worry about it. (It might however suggest "improvisation" might have been employed elsewhere on the installation as well - which may or may not have been so successful).

   - Andy.

I was concerned about the threading of the rod. Will it impact on good rod to soil contact not being a smooth surface? When driven into the ground it will need soil particles to move back to fill the gaps (troughs) in the threads as the peaks of the thread will initially make a cylindrical hole.


I installed a new rod anyway just to ensure reliability, but the question of a threaded rod was on my mind.


Z.

AJ mentioned the Irish Rules. Minimum size for hot dip galvanised steel is 10mm2 when installed vertically. There is no preference as to type as long as it is deemed capable of providing protection against corrosion and mechanical damage and has the appropriate efficacy for intended life. If any preference is implied in the Irish Rules, it would be for the provision of a foundation earth electrode.

Giving the exposed part of the rod a gentle kick if it is sticking out above ground level is another test I sometimes apply.


Andy B.

It is not wise to perform the yank test on an energised system supplying equipment with a continuous earth leakage by design, at least not with the ungloved hand ! You can end up in series with the standing current, and that ignores what happens to the exposed earthed parts  of connected kit.

A kick is less risky if there is any question .


are you sure about 10mm^2 - that is is pretty thin - a 5mm stud rod is going to meet that. (Pi R squared etc.) 10mm dia would have seemed more reliable.


I'd not worry about the thread - particles of sand and soil are scarcely a 'snug fit' to a smooth rod either,and muddy water will deposit dust like mud in the gaps


A test of Ze beats 4 aces.

Indeed, don’t yank or kick without a risk assessment ?

If you drive a new extended rod the couplers open up the hole leaving a gap around the upper rods, only the first rod to go in is actually a tight fit within the hole, if this is of any consequence is debatable.


It does mean that a new long rod that has couplers is wobbles about in the hole at the surface.


Andy Betteridge