EARTHING Sept 21, 2020 22:31:49 GMT 12
- Edited Sept 24, 2020 10:10:49 GMT 12 by Owen Y
Post by Owen Y on Sept 21, 2020 22:31:49 GMT 12
This one could be in the DIY \ Tweaks section of this forum, but it is important enough to deserve its own discussion. Recently I've been having some noise problems in the music system, even more than the usual when you have high-sensitivity speakers & tube amplification. One of the things I haven't done for a while, is to check & clean up the connection of the house main Earth conductor wire (a thick green sheathed copper wire) from the main electrical switchboard to the Earth stake (electrode) in the ground (usually outside the house). Obviously, this should only be done safely when no one in-house is operating anything electrical. Our Earth stake connection below, with Earth wire & brass clamp (after a clean-up):  The clamp removed, copper wire cleaned up (with wire-brush). The Earth stake here is a galvanised steel rod (copper clad steel or stainless steel would be better), has been sanded clean (gently with fine-grit emery paper because the zinc coating is thin).  Checking conductivity. (Not essential.)  The brass clamp contact surfaces filed clean:   I still happen to have some of this (Monster Cable) Cramolin 'contact cleaner & preservative' (which I stopped using years ago because it leaves sticky residue). I apply some of the 'preservative' to the above cleaned contact surfaces before re-assembly.  Again, it must be emphasised, the need to take care to understand that the household Earth connection must not be damaged or be left disconnected if any electrical circuits are being used.
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Post by michaelw on Sept 22, 2020 0:07:12 GMT 12
was there an audible improvement ?
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Post by colinf on Sept 22, 2020 4:14:51 GMT 12
Good idea. In the fuse box or electrical board for the house there should be a connection linking earth and neutral. Measure the difference between earth and neutral at a power socket, it should be 0 or close to it. Of course it goes without saying be careful of mains voltages! If doubtful, an electrician will be able to advise.
AMR-iFi R&D
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Post by cartridgeguyonline on Sept 22, 2020 7:42:41 GMT 12
The other thing I do with the earth stake is to give it a couple of good metric thumps with a hammer to drive it in. You shouldnt see much movement. I also water it to improve its conductivity to its surroundings. And No I have never noted an audible difference, but it doesnt cost anything and always feel virtuous afterwards.
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Pundit
Post by peter0c on Sept 22, 2020 10:38:00 GMT 12
An earthing trick I used when DXing with an Eddystone plus head amp (3 rf stages!) and had a ground plane (from which approximately 60% of the signal comes from) as well as aerial. Bury and old copper radiator (not the modern plastic things) and solder a pipe from it to the surface and periodically top it up with water. The house earth probably wouldn't be as 'clean'.
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EARTHING Sept 22, 2020 11:50:26 GMT 12
- Edited Sept 22, 2020 14:55:57 GMT 12 by Owen Y
Post by Owen Y on Sept 22, 2020 11:50:26 GMT 12
was there an audible improvement ? The appropriate question!  Yes - in this case, I hadn't attended to this for quite a few years. The improvement is akin to cleaning up your system plug & socket connections.... You hear firstly improved HF content - which enhances overall 'sharpness, definition & 'scare factor' - ie. the 'leading edges' of everything.. In what I was listening to immediately afterwards, violin definition (bowing) & orchestral 'attack' was enhanced. Interestingly, tone 'colour' seems broader, tonally smoother, finer in gradations... eg. smoother violin tone. Why should/could this be so? When you consider how the NZ home is wired, the Earth conductor (a thick 6mm2(?) single wire) goes all the way back to the switch board Earth bar, where all the power socket (& lighting) circuit Earth wires are terminated. And, as colinf says, the Neutral of the Phase/Neutral AC lines is connected to Earth at this point on the board. (I'm a little more timid about delving behind the Switch Board, but have noted colinf's comment for checking in future!) Why should this affect music signal circuits (when eg. some device PSUs are equipped with large capacitors for 'reservoir' & 'decoupling')? When you consider typical amplification circuits, the active devices are all 'swinging' AC music signals between PSU voltage & 'Ground' at zero Ohms. (Of Balanced circuits, I have little experience.) So, any resistance, or variation from zero Ohms will likely affect the music signal. Empirically, what seems to be affected firstly, is the 'lower power' end of the signal spectrum - ie. the upper freqs. And of course, this will affect the upper harmonics of all freqs.
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Post by Owen Y on Sept 22, 2020 13:33:13 GMT 12
The other thing I do with the earth stake is to give it a couple of good metric thumps with a hammer to drive it in. You shouldnt see much movement. I also water it to improve its conductivity to its surroundings. And No I have never noted an audible difference, but it doesnt cost anything and always feel virtuous afterwards. I have done the watering trick in the past. cartridgeguyonline, am I correct in thinking that galvanised steel Earth stakes are still industry standard for domestic installations in NZ? Galv steel corrodes & has a limited service life in-ground, but is Copper-clad steel commonly used?
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Post by cartridgeguyonline on Sept 22, 2020 16:12:17 GMT 12
Dont know tbh Owen. All the ones I have ever seen are Galv, In new houses they often are surrounded by concrete paths which would make watering impossible...
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Post by Owen Y on Sept 22, 2020 16:53:54 GMT 12
Some stuff here on Earth rods, different metal types. At J A Russell copper plated was around $37 ea, not a lot more than galvanised at $27. And you can see from the link above that corrosion resistance of the copper-plated is much better (in Nevada anyway, where it rains only a little, but snows quite a bit!).
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Post by Owen Y on Sept 22, 2020 21:42:59 GMT 12
More listening... I'm hearing a lot more 'scale' & 'impact' & I reckon more bandwidth top & bottom.
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Pundit
Post by neilsan on Sept 23, 2020 10:22:37 GMT 12
Just a warning Owen. It's illegal for anyone other than an electrician to work on the switchboard. And not good for your insurance! If the Main Earth or Neutral cables are disconnected for any reason and reconnected then it's meant to be inspected by an electrical inspector and signed off. Not saying I do that all the time, but I'm meant to know what I'm doing!! I tried wiring a separate earth peg just for the stereo system years ago and didn't hear any difference.Do have a separate ppt circuit for my stereo,but then ran into hum with hooking up the TV audio back for sound through the stereo. TV was on another circuit. So went back to the earth going back to normal (swbd).
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Post by cartridgeguyonline on Sept 23, 2020 10:35:06 GMT 12
Im nowhere near brave enough to venture inside our switchboard.
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Post by foveaux on Sept 23, 2020 10:47:25 GMT 12
Im nowhere near brave enough to venture inside our switchboard. nor me, I'd take-out the neighbourhood supply too...
"I see music as a lifetime affair." [Rory Gallagher]
"Free - I miss that band, but when I look back, we were very young" [Paul Rodgers]
862 posts
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EARTHING Sept 23, 2020 10:50:52 GMT 12
- Edited Sept 23, 2020 10:52:49 GMT 12 by Owen Y
Post by Owen Y on Sept 23, 2020 10:50:52 GMT 12
Hi neilsan - absolutely, only registered 'sparkies' can work on the switchboard, let's be clear about that. (I'm reluctant even to look around the back, it's such a rat's nest of hazards.) Personally, I do not install or alter any sockets or switches - even though you can legally do such work in NZ, as I understand. Some years ago, I managed to convince my Electrician (pal) to wire a few 'dedicated' power sockets for me for the listening room/lounge - ie. single lines out from the board feeding individual (double) power sockets. And fed off a couple of circuit breakers that mostly do not feed other parts of the house. I'll try sketching a layout (just for discussion). Hum - that can be a complicated & mysterious topic, deserving of its own discussion, but it is most often related to Grounding & Earthing.
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Post by Owen Y on Sept 23, 2020 11:19:25 GMT 12
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EARTHING Sept 28, 2020 19:05:02 GMT 12
- Edited Sept 28, 2020 20:47:18 GMT 12 by Owen Y
Post by Owen Y on Sept 28, 2020 19:05:02 GMT 12
Coincidentally, I read some relevant stuff in the latest issue of Electrolink magazine (I get sent this because I work in the building industry), in an article written by Athol Gibson, a NZ Electrical Inspector, that.... - Although the electrical installation is required to be tested,... " there is no requirement to test the effectiveness of the grounding, either by the installer of the system...or the inspector." - " There is no requirement or guidance on what the resistance should be as far as the medium that the earth electrode is placed in... and this resistance could be anywhere between 10 Ohms to hundreds of Ohms.". - Mr Gibson gives an example if this resistance was say 40 Ohms, then by Ohm's Law, " a maximum current of 5.75 Amps would flow (to Earth) under fault conditions" - ie. this would not blow the mains fuse & the system could be hazardous or lethal. - " Not only do we see high resistance issues through the ground, but there are many instances where the earth clamp at the electrode (earth peg) breaks from aging or mechanical damage... There are also instances where the earth wire is cut or chewed off.... These circumstances are often observed but the consequences are not understood by the property owner." - " Why do we not periodically re-verify the effectiveness of the electrode (earth peg) ?" - Mr Gibson suggests that not only should this 'fault loop impedance' test be done for new installations, but " it should also be carried out at perhaps 10 yearly intervals to ascertain the state of the effectiveness of the supply protection circuit." Well, safety aside, I can say that good Earthing affects the sound of my audio equipment. So, do take a visual inspection at least, of the state of your (green) Mains Earth Earth wire connection at your Earth ground peg. If in doubt, get an Electrician to take a look & test/remedy as necessary. Peace of mind, safety-wise AND better sound 
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