Rewire.

[pete01]

TN-S, surely?

Yep

 

[Jurassicspark]

I don't think there was anything else (other than TT) until the late 70s, was there?

Didn't we reckon that the installation from Pete's description and pictures probably is from 70/80's so I was obviously referring to that time.

However, to answer your question, I'm sure TN-S earthing was becoming increasingly common after the 60's?

We had regulations arising concerning the presence of CPC's and especially the ones linked to lighting circuits. So in 1966, and according to you, without TN-S and only TT earthing or even barely anything, I wonder to what extent they felt comfortable to see any desired change, that they enforced that regulation, considering how bad the earthing systems were back then and whether they achieved the desired result or not back then of course.

And when I say result I mean by protecting humans.

 

[Jurassicspark]

Yep

I bet it's effectively not though, and its TN-CS.

Virtually, most just treat it as a TNCS.

I've seen aluminium concentric joined to old lead paper making the supply TNCS though.

 

[JohnW2]

However, to answer your question, I'm sure TN-S earthing was becoming increasingly common after the 60's?

You seem to have misunderstood me. I was saying that I thought that for at least most of the 70s, TN-S would have been the only DNO-supplied earth (and presumably had been for decades prior to the 70s), since I thought that TN-C-S (dependent upon 'PME') did not appear until the late 70s, at the earliest.

.... So in 1966, and according to you, without TN-S and only TT earthing or even barely anything ...

See above. What you are suggesting is almost the opposite of what I was saying, namely that in 1966 TN-S was almost certainly the only type of DNO-supplied earth

 

[SUNRAY]

.

 

[securespark]

I don't think there was anything else (other than TT) until the late 70s, was there?

Yes!

TN-C-S was common in the 60s. My previous house and the rest of the estate was built in 1968 and they were all supplied thus.

 

[JohnW2]

Yes! TN-C-S was common in the 60s. My previous house and the rest of the estate was built in 1968 and they were all supplied thus.

Interesting. As I said, I didn't think it became routine practice until the late 1970s (although I understand that there were some 'local experiments' of TN-C-S in the 1930s).

Having just had a quick look around, it seems that the Code of Practice for Electricity Boards relating to the implementation of PME (obviously a requirement of TN-C-S) was first published (in "Engineering Recommendation G12/1") in 1975. I haven't yet been able to find a copy of that on-line, but I have found G12/2, published in 1982, which refers back to the 1975 document:

https://www.nienetworks.co.uk/getattachment/dee08597-ab8c-4906-8912-bd51e32980f1/ER-G12-2.pdf

 

[securespark]

As for the

So do we reckon my house was rewired sometime in the 70's? Its as the picture with solid green earth sleeve, and the original consumer unit was a 3036 wylex rewireable type.

As I have said, solid green went out on 31 December 1977.

Wylex introduced the Standard range fusebox with a brown front and fuse cover and a brown wooden back and optional (I think phenolic) backplate in 1956.

With thanks to Flameport for the images.

In the late 1970s, they introduced an ivory version with an ivory painted wooden back and an ivory front and fuse cover.

A few years later, they moved on to an all plastic design in ivory, then a few years more to this.

 

[Jurassicspark]

I don't think there was anything else (other than TT) until the late 70s, was there?

You seem to have misunderstood me. I was saying that I thought that for at least most of the 70s, TN-S would have been the only DNO-supplied earth (and presumably had been for decades prior to the 70s),

It was phrased badly, John.

 

[ebee]

Where I grew up cotton was king, towns of populations of 22,000 and up were the norm and they housing was built around 1910.
Electrics to the masses of homes was in PILC and any gas and water pipes were in lead.
Originally home towns had their own electric supply for each town, I think that they were directly or indirectly owned by the town councils.
It was inevitable that the electric supply and gas and water appeared at each home already earthed down just about completely whether intentional or not.
There are quite a few farm properties but not all of them had an electric supply some of them had their own generator often driven by a tractor or at least a tractor engine.
Houses with no electrics at all were not unknown and many of those that did have was often one socket upstairs and one socket downstairs and the lights were sometimes just a gas mantle not electric.
The mainstay of homes that did have electric were TNS by default. perhaps a few of the outlying houses and the farm properties had TT , perhaps they had TNS.
TNC-S was practically unheard of.
The incoming mains supply had a wire sweated onto the sheath and nowadays you`d look at it and think it not much bigger than fusewire by comparison (it was probably a mixture of either 2.5 or 4.0 mm at best in todays currency.
When I became a practising Electrician it did amuse me that everytime a house was rewired the DNO (Electric Board) would come to make the connection and do a few simple tests, Ins res, Ze, Zs and have a look round to visualise the points and might open the odd one or two up just to visual check the wiring and see that bonding of 6.0mm or 4.0 was in place . That was it. Whenever I asked them about the short E from the incoming cable to the customer earth terminal being less than the bonding they never baulked, it was nearly all like that.
They seemed to take the view that equalising gas, water together was more important than the equalising of that lead sheeve of the mains cable and would usually refuse to touch it unless it was literally hanging off or snapped.

As for the

As I have said, solid green went out on 31 December 1977.

Wylex introduced the Standard range fusebox with a brown front and fuse cover and a brown wooden back and optional (I think phenolic) backplate in 1956.

With thanks to Flameport for the images.

View attachment 397674


In the late 1970s, they introduced an ivory version with an ivory painted wooden back and an ivory front and fuse cover.

View attachment 397675


A few years later, they moved on to an all plastic design in ivory, then a few years more to this.

View attachment 397676

Red Rocker Down for OFF fooled a few folks LOL

 

[securespark]

Yes, indeed it did! And had a few of the "old guard" grumbling that it was wrong and why did we have to start doing stuff like "them over there"? The particular guy I was talking to was referring to the French!

 

[JohnW2]

It was phrased badly, John.

Fair enough. Needless to say, I thought (and still do) that I was fairly clear.

I find it very hard to understand how anyone who knows about these things could possibly have thought that I was suggesting that TN-S did not exist in the 1970s, given that it was the only sort of earth that the DNO could supply before the routine appearance of TN-C-S. As I presumed we all knew, TN-S was very common in 'pre-war' installations.

 

[securespark]

The incoming mains supply had a wire sweated onto the sheath and nowadays you`d look at it and think it not much bigger than fusewire by comparison (it was probably a mixture of either 2.5 or 4.0 mm at best in todays currency.
When I became a practising Electrician it did amuse me that everytime a house was rewired the DNO (Electric Board) would come to make the connection and do a few simple tests, Ins res, Ze, Zs and have a look round to visualise the points and might open the odd one or two up just to visual check the wiring and see that bonding of 6.0mm or 4.0 was in place . That was it. Whenever I asked them about the short E from the incoming cable to the customer earth terminal being less than the bonding they never baulked, it was nearly all like that.
They seemed to take the view that equalising gas, water together was more important than the equalising of that lead sheeve of the mains cable and would usually refuse to touch it unless it was literally hanging off or snapped.

I had visits from the leccy board to do checks before they would connect me up and they would check the bonding and such-like.

When I did a shower for my Ma in 1986 (a Triton T100E in 10 milli with a 45 or 50A MK 2G switch and a 45A MCB), the guy refused to connect it, saying that the bonding was insufficient and the MCB should be changed for a cartridge fuse....

So, I pulled in a new length of 10 milli bonding and swapped the MCB for a B88.

He came back later and happily signed it off.

 

[JohnW2]

... As I have said, solid green went out on 31 December 1977.

Yes, regs-wise it did. However, as I mentioned, I saw solid green sleeving being used much later than that, I suspect because those doing it had 'vans full of the stuff' and didn't want to throw it away!

One also has to remember that there is sometimes debate as to whether bare CPCs need sleeving at all - so maybe the guys with lots of green sleeving felt that, if even the need for any sleeving was 'debatable', then perhaps the exact colour they used wasn't all that important?

 

[securespark]

Talking of earthing at the intake, I had a few battles getting them sorted out in my career.

Including one on a TN-C-S supply that was in 4 figures.

I don't think the DNO would believe me, but after two calls they sent someone out. I couldn't leave the property until It was sorted and had to turn the leccy off. It was one of those hybrid heads where the neutral and earth could be separated so you use it as TN-S and the link was loose, so the loop reading was crazy high.

I've had subterranean TT supplies in Staffs where the rod is under the floor, sunk in concrete! And, equally bad, a cottage in Buxton where the conductor from the rod was run up the garden and the end, stripped back a couple of inches, was shoved in the lawn and the husband told the widow to water the lawn every day.....that reading was crazy high too!

I used to have photos of these and lots of other interesting shots, but sadly, they were stored with Photo bucket and I lost them.

Basically, if the DNO supplied an earth connection to the property originally, they have a duty to maintain it, but they often try to wriggle out of it.

Several times, they fitted a pipe clamp to provide a connection for my customers on PILC cable!

The last time this happened must have been around 2011-2012.

Must be frowned upon now, I thought they were supposed to use the wrap around springs these days (constant pressure springs?).