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What is the cable coming out bottom-left of the photo "Cutout Earth Block Bottom Underside View.jpg" as it looks as if the outer sheath is begining to perish?
Good Afternoon, It is the cable supplying the Cooker circuit.

They are all PVC cables what you see on the cables is dust.
I just didn't think about cleaning them before taking the photos/video.
The same goes for the tails coming from the bottom of the cutout in the video.
I assure you though, dust is all it is.

Regards
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They are all PVC cables what you see on the cables is dust.
I just didn't think about cleaning them before taking the photos/video.
The same goes for the tails coming from the bottom of the cutout in the video.
I assure you though, dust is all it is.
Probably is just dust or spider's web, it was this bit that worried me:
House Earthing TN-S or TT.... cable-picture - EletriciansForums.net
Again, probably with a quick clean using an old pain brush or similar it would look fine.
 
If it has been fed with a split concentric cable then it will be TNS.

Overhead TNS distribution is rare but it does exist, so it is possible that this is what you have.

I know the type of cutout you are describing, that plastic cover does come off t reveal the earth terminal, but you do need to get it confirmed that it as a suitable earth before connecting to it.

Your best/safest bet is to contact the DNO to get them to confirm what type of eartjing system is provided. You may have to get them to visit to give a satisfactory answer as they might just say TT over the phone to get away without doing anything.
But remeber you probably won't get anywhere with a non-emergency callout at the moment.
Good Evening
Although You you and pc1966 have been very helpful, which I am extremely grateful for, I have attached some drawn diagrams of how things have been over time.
(BTW, the current CU was installed more around 1996).
You can see the layout pre 1990, 1990-1996 (with no effective Earthing!!!) and the current layout.
My idea of what happened (however I cannot be totally sure) is when the house was initially rewired in the early 80s with the 3036 CU, is my father (although he didn't re-wire the actual house himself) installed a small (obviously ineffective, in dry rocky ground) *Earth rod outside, but unaware of an Earth *already provided from the overhead supply.
When the new cable and cutout was installed in 1990, and he mentioned to the DNO chap he had previously installed an Earth rod, he claimed the DNO chap suggested there was an Earth on the poles supplying the house, and with regard to been told this, probably *assumed the Earth was connected and in place (however, the Earth cable from the 3036 CU was left dangling, since if it was meant to be connected to the DNO Earth, it was too short to reach the new cutout (and of course the 'pinch' mark left in the bared end I tend to remember).
*my father, just like many others, is not very familiar with electrical circuitry, so I do not consider this as his fault in any way.
The Earth rod and cable in use is still the same, but the cable was relocated lower down when the new CU was installed.
Please see the diagrams for more information.
PS I have used the colours Red, Black and Green to denote Line, Neutral and Earth cables respectively.

Kind regards.
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Probably is just dust or spider's web, it was this bit that worried me:
View attachment 58106
Again, probably with a quick clean using an old pain brush or similar it would look fine.
HI,
Yes, there is a load of dust and spiders webs around there.

You and davesparks have been very helpful.

I have just replied to one of davesparks' posts with some drawn diagrams of how I tend to remember things over time, with a few explanations on them (although generally what I have said earlier). Please refer to the diagrams.

Kind Regards.
 

Attachments

  • House Earthing TN-S or TT.... Distribution Layout Pre 1990 - EletriciansForums.net
    Distribution Layout Pre 1990.jpg
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  • House Earthing TN-S or TT.... Distribution Layout 1990-1996 - EletriciansForums.net
    Distribution Layout 1990-1996.jpg
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  • House Earthing TN-S or TT.... Distribution Layout 1996-Present - EletriciansForums.net
    Distribution Layout 1996-Present.jpg
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wire the actual house himself) installed a small (obviously ineffective, in dry rocky ground) *Earth rod outside, but unaware of an Earth *already provided from the overhead supply.
Has a more effective local earth rod now been installed?

Unless you are getting a rod impedance reliably below 200 ohms (less is better, obviously) then you ought to peruse the DNO about the suitability of their earth and arrange for them to connect to it.
 
Has a more effective local earth rod now been installed?

Unless you are getting a rod impedance reliably below 200 ohms (less is better, obviously) then you ought to peruse the DNO about the suitability of their earth and arrange for them to connect to it.
It is still the same Earth rod in place, although showing no signs of corrosion etc.
Perhaps I should not have stated 'obviously ineffective', however, although one cannot be sure without a Professional Loop Impedance instrument to measure the Ze and therefore give a specific numerical Ze value, the ground the rod is situated in is fairly dry, rocky and is nowhere near within the 'General Mass' of earth, in line with the transformer (which supplies the OH line) Earth rod.
If you walk from the back of the house up to the transformer supplying the OH LV supply, it is a steep-ish uphill route, and the land consists of many rocks within the ground etc, so a very rocky place.

The lower down village, supplied from a totally different Network, is all PME, overhead supply. There is a pole in the road, near the bottom of the very long driveway to the house, with an Earth electrode running down from it (probably part of the PME 'Multiple' Earthing), but again this is on a much lower down level than the mass of earth the house rod is situated in. Again, the driveway, land etc in between are very rocky and dry places.
On a side note, the Loop Value on a Kewtech 107 Socket Tester lit up as 'URGENT CHECK', i.e. over 93 Ohms as indicated in the Manufacturers Instructions (although I am aware personal opinions vary on such instruments).

If the chance should occur, I will definitely enquire regarding the DNO Earth.
In 2009, a visit from the DNO was made to the property to notify my parents that the cable running to the chimney pot (from the pole) is required to be removed and lowered from the chimney pot.
Then either last year/year before another visit was made from them (yes it was 9/10 years since previously hearing from them) they visited again.
If there is another visit, I will try and enquire then.
Saying that, many bare OH lines in the area have been converted to the new twisted insulated (possibly sheathed as well?) conductors, so although a bit off-topic, if they end up changing the entire OH supply to the property, they won't use TN-S Earthing with a new line will they?, it will possibly be a case of a split-con cable connected to a TN-C-S Network.

Regards
 
You have no idea how lucky you are to have a TN-S supply (at least the option appears to be there), one where the 11kv is also run on two insulated wires. I can't say for sure, but I'd imagine this supply would eventually go to TN-C-S when the secondary is upgraded as is typical today.
 
of earth the house rod is situated in. Again, the driveway, land etc in between are very rocky and dry places.
On a side note, the Loop Value on a Kewtech 107 Socket Tester lit up as 'URGENT CHECK', i.e. over 93 Ohms as indicated in the Manufacturers Instructions (although I am aware personal opinions vary on such instruments).
The photos show plenty of vegetation around, so it is not as dry and rocky as some locations!

Still for a decent earth rod you probably need it to go down something like 2m or so. You can get 1m long SDS drill bits that would allow and easy-ish way to get down 1m depth and then see if you can drive a rod down further. Of course, you should always be aware of the possibility of hitting a pipe or buried cable (cable less likely I guess) and what some folks advise is to dig down 1m or so manually (e.g. fence post digging tool) as by that depth you ought to have found any utility pipes, etc.

Another option to get a better Earth is to make a deep but farily narrow hole (as deep as you can, basically) for the rod to be driven in then fill it with conductive concrete. That fills out in to the gaps and tends to retain moisture a bit better keeping the path to "true Earth" a bit better. You might find this cheaper elsewhere, but this is the idea:

Opinions on socket testers in these parts do vary, but the Kewtech Loopcheck 107 is actually a fairly good one. By "vary" I mean folk think they are pants, which is true if you compare it to a MFT operated by someone knowledgable, but as an affordable test for a DIY / home owner it s a damn sight better than nothing. The cheaper testers (£10 region) suffer from not detecting a high-Z earth, only one that is totally disconnected (above tens of kOhm in most cases).

So they won't detect some types of serious fault. Basically they prove bad, not good. If one tells you there is a problem then you need to do something about it, however if it says all is fine you could be fooled as it has not picked up on something like a high-R earth.

Also none of them pick out a N-E swap. If the socket is RCD protected that is quickly detected in use, but a lot of homes still lack RCD protection so not being able to show that fault is another grey area. Now usually the R1+R2 test with L-E shorted at the CU would reveal reversed polarity, but DIY socket change would not (and should not) be doing that, or a wander lead to check R2 would show it if mains was off (so N-E open at the house isolation switch), but again that is not a DIY/home owner sort of procedure.
 
You have no idea how lucky you are to have a TN-S supply (at least the option appears to be there), one where the 11kv is also run on two insulated wires. I can't say for sure, but I'd imagine this supply would eventually go to TN-C-S when the secondary is upgraded as is typical today.
HI
The thought of been lucky to have the TN-S (although not currently used) has crossed my mind a few times.
The OH Line I was told was installed in the early 1960s, the first time my parents cottage (and the other properties supplied from the same Transformer) had electricity installed.
The houses in the village just below (mentioned in a previous post) did not have electricity until the 1950s (when a row of 10 council houses were built) and the houses were supplied overhead with two cables (L&N) and employed a TT system, I think via the mains water pipe!!! (I am aware it was once permitted) although since the last 25+ years all cables supplying the village houses have been replace with ordinary concentric cable and PME'd.
So yes, I fully understand where you are coming from.
I have therefore often considered, for an Earth to be provided to my parents cottage (and the two other properties) initially at the time (early 1960s) of the OH Line being installed was, in the very remote country concerned, a PRIVILEGE.
To put this another way, it is a shame for a solely separate Earth cable on the pole to be there, serving no purpose whatsoever, when possibly available for use (although it only serves a purpose for Earth Leakage faults, which are probably a very rare occurrence in practice, but I consider that being beside the point).

Kind Regards

[automerge]1589849324[/automerge]

[automerge]1589849542[/automerge]
HI
The thought of been lucky to have the TN-S (although not currently used) has crossed my mind a few times.
The OH Line I was told was installed in the early 1960s, the first time my parents cottage (and the other properties supplied from the same Transformer) had electricity installed.
The houses in the village just below (mentioned in a previous post) did not have electricity until the 1950s (when a row of 10 council houses were built) and the houses were supplied overhead with two cables (L&N) and employed a TT system, I think via the mains water pipe!!! (I am aware it was once permitted) although since the last 25+ years all cables supplying the village houses have been replace with ordinary concentric cable and PME'd.
So yes, I fully understand where you are coming from.
I have therefore often considered, for an Earth to be provided to my parents cottage (and the two other properties) initially at the time (early 1960s) of the OH Line being installed was, in the very remote country concerned, a PRIVILEGE.
To put this another way, it is a shame for a solely separate Earth cable on the pole to be there, serving no purpose whatsoever, when possibly available for use (although it only serves a purpose for Earth Leakage faults, which are probably a very rare occurrence in practice, but I consider that being beside the point).

Kind Regards

[automerge]1589849324[/automerge]
Also, if the OH Earth had been suitable for use all along, then that possibly means the necessity to fork out on the cost of the TD RCD in the CU currently installed was not justified! :angry:
[automerge]1589850941[/automerge]
The photos show plenty of vegetation around, so it is not as dry and rocky as some locations!

HI
I understand what you are saying, but the Earth rod is directly outside the house in the garden right by the porch wall, in a fairly sheltered location.

NB I am not implying that you have misunderstood the photos, I just wasn't sure of your post above, but to clarify, the photos shown are the area between the Transformer and the cottage i.e. all photos shown are behind the cottage, I haven't posted any photos from between the front of the cottage and the road.

Regards
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The photos show plenty of vegetation around, so it is not as dry and rocky as some locations!

HI
I understand what you are saying, but the Earth rod is directly outside the house in the garden right by the porch wall, in a fairly sheltered location.

NB I am not implying that you have misunderstood the photos, I just wasn't sure of your post above, but to clarify, the photos shown are the area between the Transformer and the cottage i.e. all photos shown are behind the cottage, I haven't posted any photos from between the front of the cottage and the road.

Regards

Sorry, something has gone wrong with the quoting







HI
The thought of been lucky to have the TN-S (although not currently used) has crossed my mind a few times.
The OH Line I was told was installed in the early 1960s, the first time my parents cottage (and the other properties supplied from the same Transformer) had electricity installed.
The houses in the village just below (mentioned in a previous post) did not have electricity until the 1950s (when a row of 10 council houses were built) and the houses were supplied overhead with two cables (L&N) and employed a TT system, I think via the mains water pipe!!! (I am aware it was once permitted) although since the last 25+ years all cables supplying the village houses have been replace with ordinary concentric cable and PME'd.
So yes, I fully understand where you are coming from.
I have therefore often considered, for an Earth to be provided to my parents cottage (and the two other properties) initially at the time (early 1960s) of the OH Line being installed was, in the very remote country concerned, a PRIVILEGE.
To put this another way, it is a shame for a solely separate Earth cable on the pole to be there, serving no purpose whatsoever, when possibly available for use (although it only serves a purpose for Earth Leakage faults, which are probably a very rare occurrence in practice, but I consider that being beside the point).

Kind Regards
HI
The thought of been lucky to have the TN-S (although not currently used) has crossed my mind a few times.
The OH Line I was told was installed in the early 1960s, the first time my parents cottage (and the other properties supplied from the same Transformer) had electricity installed.
The houses in the village just below (mentioned in a previous post) did not have electricity until the 1950s (when a row of 10 council houses were built) and the houses were supplied overhead with two cables (L&N) and employed a TT system, I think via the mains water pipe!!! (I am aware it was once permitted) although since the last 25+ years all cables supplying the village houses have been replace with ordinary concentric cable and PME'd.
So yes, I fully understand where you are coming from.
I have therefore often considered, for an Earth to be provided to my parents cottage (and the two other properties) initially at the time (early 1960s) of the OH Line being installed was, in the very remote country concerned, a PRIVILEGE.
To put this another way, it is a shame for a solely separate Earth cable on the pole to be there, serving no purpose whatsoever, when possibly available for use (although it only serves a purpose for Earth Leakage faults, which are probably a very rare occurrence in practice, but I consider that being beside the point).

Kind Regards

[automerge]1589849324[/automerge]

[automerge]1589849542[/automerge]

Also, if the OH Earth had been suitable for use all along, then that possibly means the necessity to fork out on the cost of the TD RCD in the CU currently installed was not justified! :angry:
[automerge]1589850941[/automerge]


[automerge]1589849324[/automerge]

[automerge]1589849542[/automerge]

Also, if the OH Earth had been suitable for use all along, then that possibly means the necessity to fork out on the cost of the TD RCD in the CU currently installed was not justified! :angry:
[automerge]1589850941[/automerge]
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I don't know what's happening, but the quoting is going all wrong for some reason.

Regards
 
Last edited:
HI
The thought of been lucky to have the TN-S (although not currently used) has crossed my mind a few times.
The OH Line I was told was installed in the early 1960s, the first time my parents cottage (and the other properties supplied from the same Transformer) had electricity installed.
The houses in the village just below (mentioned in a previous post) did not have electricity until the 1950s (when a row of 10 council houses were built) and the houses were supplied overhead with two cables (L&N) and employed a TT system, I think via the mains water pipe!!! (I am aware it was once permitted) although since the last 25+ years all cables supplying the village houses have been replace with ordinary concentric cable and PME'd.
So yes, I fully understand where you are coming from.
I have therefore often considered, for an Earth to be provided to my parents cottage (and the two other properties) initially at the time (early 1960s) of the OH Line being installed was, in the very remote country concerned, a PRIVILEGE.


Massive privilege. TT and TN-C-S are simply comprises (trade offs between various disadvantages/risks) in a world where utilities refuse to provide more than the bare minimum number of conductors that will light a light bulb or spin a motor. If I had to choose between IT, TT, TN-C-S and TN-S, I would hands down choose TN-S.

Low Z fault path, no stray voltage or current, no shock danger from a broken neutral (PEN), no danger from a failed RCD during an indirect contact fault, reduced line noise in old audio equipment... I'm forgetting about a half dozen other advantages.

In the United States we have it way worse, in that not only does our MEN serve as an LV PEN, but also as a PEN for the MV system. Stray voltage is a big problem especially on dairy farms, swimming pools, caravans and the like.



To put this another way, it is a shame for a solely separate Earth cable on the pole to be there, serving no purpose whatsoever, when possibly available for use (although it only serves a purpose for Earth Leakage faults, which are probably a very rare occurrence in practice, but I consider that being beside the point).

That extra wire is a blessing that I wish everyone on earth could experience.



Also, if the OH Earth had been suitable for use all along, then that possibly means the necessity to fork out on the cost of the TD RCD in the CU currently installed was not justified! :angry:

If the PE coming in was good, then no, I don't think the RCD was needed back then.

I don't know what's happening, but the quoting is going all wrong for some reason.

Regards

Its ok, this has happened to me on other sites before :)
 
If I had to choose between IT, TT, TN-C-S and TN-S, I would hands down choose TN-S.

Low Z fault path, no stray voltage or current, no shock danger from a broken neutral (PEN), no danger from a failed RCD during an indirect contact fault, reduced line noise in old audio equipment... I'm forgetting about a half dozen other advantages.
Yes, certainly my view on the matter as well!

The TN-C-S option would not be so bad if it were a ring circuit (so no single PEN break causing 'earth' to rise up) but I don't think that is ever done (ring on HV yes).

In the United States we have it way worse, in that not only does our MEN serve as an LV PEN, but also as a PEN for the MV system. Stray voltage is a big problem especially on dairy farms, swimming pools, caravans and the like.
It is not my area of expertise, but I think historically the UK has shared MV and LV earths at some transformers, but only if the substation Ra was below 1 ohm. However, I don't think that is allowed any more on new setups?
 

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