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Ali Tait
05-05-2009, 22:21
In the interests of keeping people safe and informed, please read this thread,particularly post 13,which will make clear the safety issues in making an extra earth for your system via a copper spike buried in the garden.

http://wduk.worldomain.net/forum/showthread.php?t=2511&page=2

Spectral Morn
05-05-2009, 22:30
Thanks Ali for the link.

Always wise to keep it safe get qualified advice and help.



Regards D S D L

Ali Tait
05-05-2009, 22:37
Just want to keep peeps safe! :)

Barry
06-05-2009, 01:10
In the interests of keeping people safe and informed, please read this thread, particularly post 13,which will make clear the safety issues in making an extra earth for your system via a copper spike buried in the garden.

http://wduk.worldomain.net/forum/showthread.php?t=2511&page=2

Looks like you beat me to it, Ali.

I had previously read this thread on the World Designs forum and realised its pertinance, but didn't know how to reference it.

Regards
Barry

Ali Tait
06-05-2009, 07:38
Just laziness really.I'm not the world's fastsest typist so it was easier to link to this rather than spend half the night typing a long explanation!

Barry
06-05-2009, 08:43
Just laziness really.I'm not the world's fastsest typist so it was easier to link to this rather than spend half the night typing a long explanation!

Hello Ali,

I would be very interested to learn something of the theory behind the latest regulations concerning electrical earthing. However I do not want to cause confusion and create possible misunderstanding at the present time, over what is a very important subject. Perhaps when things have settled down, we could discuss this if you are agreeable. As a designer of high voltage substations you clearly know what you are talking about.

Thanks

Barry

Barry
06-05-2009, 09:11
Hi Ali,
I have just read the link quoted in Martin T's latest posting:

www.acoustica.org.uk/t/earth.html .

I now better understand the reasons for concern, so won't be bothering you for explanations.

Regards
Barry

Ali Tait
06-05-2009, 12:20
Hi Barry,
Yes that article explains it better than I could.I will freely admit to being more knowledgeable about the high voltage side of things than domestic electrical systems.I do however have a pretty good theoretical knowledge of such things.

Mike Reed
06-05-2009, 18:58
I thought that putting in an earthing spike had been de rigeur for serious audiophiles for a couple of decades now.

My first attempt in the early eighties was to drive a copper rod THROUGH the wine cellar wall, which was adjacent to the mains board. It was, understandably, slightly damp there anyway.

Unfortunately, I also believe I pierced the sewerage pipe outside, as the room pen and inked a bit thereafter; wine and beer was ok, though!

Mike
06-05-2009, 19:07
My first attempt in the early eighties was to drive a copper rod THROUGH the wine cellar wall, which was adjacent to the mains board. It was, understandably, slightly damp there anyway.

Unfortunately, I also believe I pierced the sewerage pipe outside, as the room pen and inked a bit thereafter; wine and beer was ok, though!

And that folks, is why you should dig a trench and bury them horizontally! :)

Mike Reed
07-05-2009, 13:24
Gosh! Why didn't I think of that? Massive thickness of Victorian foundation concrete; t'would have been a doddle!!!!!

Yes, if you're not sure what lies under your garden (which is where most people put one, I guess), a horizontal trench is safer.

However, this method can also be destructive of established plants, and the jury's out as to whether it provides a better earth horizontally or vertically. Broad as it is long, I s'pose! A position exposed to precipitation is advisable, though, for a better earth continuity, especially as one is most likely to position the spike close to the outer walls.

Barry
07-05-2009, 14:18
Gosh! Why didn't I think of that? Massive thickness of Victorian foundation concrete; t'would have been a doddle!!!!!

Yes, if you're not sure what lies under your garden (which is where most people put one, I guess), a horizontal trench is safer.

However, this method can also be destructive of established plants, and the jury's out as to whether it provides a better earth horizontally or vertically. Broad as it is long, I s'pose! A position exposed to precipitation is advisable, though, for a better earth continuity, especially as one is most likely to position the spike close to the outer walls.

Actually it does make a difference; this is a subject of continued research especially in conection with the design of lightning conductors and the grounding arrangements for high frequency antennae. I suspect, however, that for grounding spikes being discussed here, the actual orientation is less of an issue than the local conductivity of the neighbouring soil.

For those that might be interested see:

www.copperinfo.co.uk/power-quality/downloads/pqug/631-earthing-systems-fundamentals-of-calculation.pdf

Regards

Barry

The Grand Wazoo
07-05-2009, 18:39
Actually it does make a difference; this is a subject of continued research especially in conection with the design of lightning conductors and the grounding arrangements for high frequency antennae. I suspect, however, that for grounding spikes being discussed here, the actual orientation is less of an issue than the local conductivity of the neighbouring soil.



I would think that both factors would be significant as surface soil is almost always of a lower moisture content that of substrate soil. Sandy soils are very free draining & will be significantly less conductive.

Mike Reed
07-05-2009, 19:10
I would think that both factors would be significant as surface soil is almost always of a lower moisture content that of substrate soil. Sandy soils are very free draining & will be significantly less conductive.


Based upon this premise, maybe a shaft would be preferable to a trench!!!!!

Once upon a time, this hobby of ours was so uncomplicated. There were ONLY valve amps; ONLY m.m. cartridges (I think), mostly DIY, Wharfedale & Leak speakers and Goldring or Garrard for t/ts. Cables? Uh-uh! Supports? Nah! Mains and earthing tweaks? Didn't even have 3-pin mains in most houses.

I get my rose-tinted specs. from Specsavers, btw. Bullet-proof vest for expected fusillade from members with better memories or hands-on experience.

Barry
07-05-2009, 19:15
I would think that both factors would be significant as surface soil is almost always of a lower moisture content that of substrate soil. Sandy soils are very free draining & will be significantly less conductive.

As a forestry warden, you clearly know a lot more about soil than I. Not wishing in any way to diminish the importance of conductivity, I am however curious at what depth 'surface soil' becomes 'substrate soil'. Assuming the grounding rods under discussion are no more than 1m long, vertical deployment could be less effective than horizontal deployment. Again I have assumed that in the latter arrangement, the rod would be buried at least 30cm deep, preferably deeper.

My remarks on the difference between horizontal or vertical deployment, and also on how many spikes are used and how they are connected together ('star' or 'daisy-chain'), really only come into play at high (radio) frequencies, where not only the resistance but the inductance is important. But all of this is of little importance at mains frequencies, provided of course that the soil is a reasonably good conductor.

Regards

Barry

Spectral Morn
07-05-2009, 19:53
As our group of houses are built on reclaimed land.....the sea/beach was once here....

The garden is a layer of top soil, thicker clay and sand (lots of sand). Last summer I built a fence just after I lost my job and during the post hole digging found sea shells. I have seen an early Victorian painting of our area and the sea was ruling where our street is now. So earth spikes are no good for me then....:lol:


Regards D S D L

The Grand Wazoo
07-05-2009, 20:21
As a forestry warden, you clearly know a lot more about soil than me. Not wishing in any way to diminish the importance of conductivity, I am however curious at what depth 'surface soil' becomes 'substrate soil'.

There's no hard & fast rule here, and in fact, the terms I used oversimplify the whole thing enormously - I just used them to put the point across. There are so many variables at play that you couldn't make a generalisation.

However, that's what I'll do!

Up to a point, the deeper you go, the moisture content increases, mainly due to evaporation at the higher levels. Levels & composition of salinity and dissolved nutrients will also have a great effect on conductivity. For example: Nitrogen will not conduct electricity - so peeing on your earth rod will make it worse! (nitrogen fertilisers are made from urea)........I could go on but this is getting really esoteric for a hi-fi forum!!


Assuming the grounding rods under discussion are no more than 1m long, vertical deployment could be less effective than horizontal deployment. Again I have assumed that in the latter arrangement, the rod would be buried at least 30cm deep, preferably deeper.

I'd imagine that in most soils, you'd be getting into the permanently wet stuff at 1 metre and 30 cm would give variable results - don't know for sure.

Barry
08-05-2009, 01:32
...........

Up to a point, the deeper you go, the moisture content increases, mainly due to evaporation at the higher levels. Levels & composition of salinity and dissolved nutrients will also have a great effect on conductivity. For example: Nitrogen will not conduct electricity - so peeing on your earth rod will make it worse! (nitrogen fertilisers are made from urea)........I could go on but this is getting really esoteric for a hi-fi forum!!

I'd imagine that in most soils, you'd be getting into the permanently wet stuff at 1 metre and 30 cm would give variable results - don't know for sure.

Hello Chris,

I trust you didn't think I was doubting your expert knowledge, I was merely curious as to what depth a grounding stake should be buried or driven.

From what you say it would seem that a 1m stake, driven vertically into the ground ought to be sufficient, as the current would flow cylindrically away from the length and hemispherically away from the tip, whereas the same stake buried horizontally 1m deep would be better.

Seeing that urine is at least 95% water, with a typical pH < 7, won't peeing on a ground stake temporarily improve the conductivity of the upper soil ? - but as you rightly say, all this is deviating away from topics this forum was set up to discuss.

Regards

Barry

The Grand Wazoo
08-05-2009, 07:31
Hello Chris,

I trust you didn't think I was doubting your expert knowledge, I was merely curious as to what depth a grounding stake should be buried or driven.

Well, actually, I don't regard myself as an expert - so doubt away! Soil science is a field in itself (no pun intended, but now I think about it, it's pretty funny) & I only address it when I have to.


From what you say it would seem that a 1m stake, driven vertically into the ground ought to be sufficient, as the current would flow cylindrically away from the length and hemispherically away from the tip, whereas the same stake buried horizontally 1m deep would be better.

I'm not sure I understand your thinking here - I'd have thought horizontal orientation would waste some of the (non-electrical) potential of the surface area of the spike because more of it's surface area would be acting on the upper layer.


Seeing that urine is at least 95% water, with a typical pH < 7, won't peeing on a ground stake temporarily improve the conductivity of the upper soil ? - but as you rightly say, all this is deviating away from topics this forum was set up to discuss.

Temporarily is the key word here - the water will dissipate, but the nitrogen will remain. It hangs around in soils which is why Britain is rapidly being swathed in NVZ's & NSZ's (nitrate vulnerable and sensitive zones) by the Environment Agency who limit the quantity of nitrogen based fertilisers that farmers can use - because the levels have built up over time.

Mike Reed
08-05-2009, 08:40
Temporarily is the key word here - the water will dissipate, but the nitrogen will remain. It hangs around in soils which is why Britain is rapidly being swathed in NVZ's & NSZ's (nitrate vulnerable and sensitive zones) by the Environment Agency who limit the quantity of nitrogen based fertilisers that farmers can use - because the levels have built up over time.[/QUOTE]


Unusually, it seems that the piss is being left, rather than taken.

Seems there are (were) two concurrent earthing threads going, so maybe it's time this one goes to ground, as it were.

Barry
08-05-2009, 13:22
.........

I'm not sure I understand your thinking here - I'd have thought horizontal orientation would waste some of the (non-electrical) potential of the surface area of the spike because more of it's surface area would be acting on the upper layer.


On reflection I think that the efficacy of either orientation will be compromised, if used in soil in which there is a significant variation of conductivity with depth. In the case of vertical deployment, current flows away from the rod in a radial fashion, so the equipotential contours around the rod are circles whose radius decreases with depth as the conductivity increases. With horizontal deployment, the equipotential contours are 'egg-shaped' and will be closer together (think of contours on a map) on the underside of the rod, again where the conductivity is better.

After this consideration, it is now no longer clear to me which of the two options best utilise the grounding rod's surface area, when employed in soil of varying conductivity. To give a definitive answer, I would need to know the conductivity gradient with depth and use software to which I no longer have access - or I might simply consult someone in the lightning conductor business. But it seems that supplementing the domestic earthing arrangements with such a rod is ill advised, so this discussion, whilst theoretically interesting, is somewhat moot.

Finally (and I promise that this is my last word on the subject), might I suggest the use of camel pee. The camel is so well adapted to conserve water, that it's urine is full of salt. Not good for plants - but with all those electrolytes, a better conductor than sea water.

Regards

Barry

Barry
08-05-2009, 13:25
.....

Seems there are (were) two concurrent earthing threads going, so maybe it's time this one goes to ground, as it were.

Agreed, see the last paragraph in my reply to Chris (The Grand Wazoo).

Barry

The Grand Wazoo
08-05-2009, 15:49
..............I'll get me camel

Beechwoods
09-05-2009, 06:03
I don't want to take the piss, but I hope no-ones got the hump with this one... ;)

Ali Tait
09-05-2009, 08:24
A camel would be very helpful for working out which way is best.According to Terry Pratchett,they are the greatest mathematitions in existence...

Sonority
25-05-2009, 09:17
A bit late here, but you may find reading this site very useful.
It has a ton of information, and can lead to other things being searched for - such as 'Bentonite' (cat litter to most folk) as being a superb backfill for earthing rods.

Anyways, I found it very useful and helpful,

http://lecglobal.com/solutions/grounding/chem-rod/