A real moan tonight...

[JohnW2]

I'm with you all the way John.

It's reassuring to hear that it's not just me!

I'm guessing, and this really is guessing without any clues to any facts, I'm guessing it's all down to the accumulation of leakage, capacitance, inductance etc of every part of the network to earth...

That's the nearest to a credible explanation, but I don't honestly think that it is really credible that you could light a mains-voltage bulb with that, do you?

It certainly would be easier to 'understand' if there were a fault in the supply neutral, maybe just affecting a small proportion of the consumers being served by the tranny.

Kind Regards, John

 

[SUNRAY]

Noticed the Black core is Neutral, fairly common in the early days, luckily taped Blue as can easily catch you out if ever reconnecting.

The blue tape is mine after I took it out to change the gland.

Yes initiallly in harmonisation I went with black to keep some consistancy with old colours, as you say it was quite common. Others seemed to prefer grey neutral which I didn't really understand until we extended some RYB SWA's with new colours and it would have been soooo wrong to join black/blue & grey/yellow. In fact I have come across earth/neutral flips for this reason.

 

[Risteard]

I'm not sure why you picked on me. If you look back at the four pages of this thread, you will see that all I was doing (at least partially to avoid confusion) was continuing to use the same language as had everyone (including the OP) - namely to talk of the 'earth' derived from a local earth electrode as a 'TT earth'. Everyone, including you, knew exactly what everyone involved in the discussion meant, and I'm sure that none of them thought, or think, that adding what are effectively extraneous-c-ps to a TN installation turns it into a 'TT' one.

I didn't see the other posts. Believe it or not I don't read every post on the forum.

However if you like I will search through to find any other objectionable posts and I will duly chastise those who posted them.

 

[SUNRAY]

This is what I think is the situation. The Neutral from the substation extends into the area where the ground potential is being pulled by the star point potential to be different from the ground potential that the sub station Neutral is connected to.

The loads at the consumer's location are the totals of several consumers and are not equal to each other.

View attachment 204091

It's feasible scenario, I'd have expected the unstable voltages to have been reported before unless the fault was coincident with my visit.

My current thinking is more like this:

Broken earths path with 'random leakage' to earth shown in pink.

Again I'll stress this is all guess work on my part.

 

[bernardgreen]

My current thinking is more like this:

That has potential ( Sorry )

It is possible that two phases could have been leaking to different parts of the ground.

Going deeper

The ground we stick electrodes into is far from being a simple conductive mass. Apply voltages to it and it behaves like a complex 3 dimensional network of interconnecting resistors. With a bit of rectification added to the complexity.

Back in the 1960's I was experimenting with the use of ground currents for carrying speech. All the notes I made have long gone but I do clearly recall that reality and theory did not always agree, ( though later the theory was improved and there was less disagreement ).

The original set up in the back garden was this arrangement. Good communication.

but these arrangements also provided reasonable transmission.

Experiments ended when we moved to a flat with no garden.


A useful reference to communication using ground currents can found here http://bcra.org.uk/creg/heyphone/

 

[SUNRAY]

That has potential ( Sorry )

It is possible that two phases could have been leaking to different parts of the ground.

Going deeper

The ground we stick electrodes into is far from being a simple conductive mass. Apply voltages to it and it behaves like a complex 3 dimensional network of interconnecting resistors. With a bit of rectification added to the complexity.

Back in the 1960's I was experimenting with the use of ground currents for carrying speech. All the notes I made have long gone but I do clearly recall that reality and theory did not always agree, ( though later the theory was improved and there was less disagreement ).

The original set up in the back garden was this arrangement. Good communication.

View attachment 204111

but these arrangements also provided reasonable transmission.

View attachment 204113

Experiments ended when we moved to a flat with no garden.


A useful reference to communication using ground currents can found here http://bcra.org.uk/creg/heyphone/

I did similar experiments shortly after you, mine started with a neighbour 3 door along so I'll guess about 25 to 30m in very wet clay and to be honest it wasn't very successful until one ends spikes were moved further apart, I can't recall whether TX or RX. Ended up with spikes spread between front and back gardens.
Then included another location about 3/4 mile away at a friends house with no success but a further mile worked after a fashion to another friends house... and then we were back at school.

 

[SUNRAY]

A little update on this one:

I've been out this morning and, as it's been raining hard, opted to take a slighly different route home to visit this customer, she was right in the middle of pouring coffee as i walked past the kitchen window, by the time I got to the front door a cup had been poured for me and presented it at the door. She was rambling about the sucess of my repair but after power was restored one of her neighbours had issues with with some things not working, electric shocks from taps etc and tripping which hadn't been a problem before. Their electrician was called in, he "updated the fuse box and did some other work". To fix the problem which had only become apparent after the supply had been fixed.

Looking at the pole they are on different phases. It makes me wonder if a problem there...was pulling the wrong part of the floating supply to earth.

EDIT: To clarify my post

 

[securespark]

Are you going to remove the return wire to save confusion later?

Methinks qualified sparks would not be confused.

 

[JohnW2]

Methinks qualified sparks would not be confused.

One would hope so - but, unfortunately, I fear that the word "qualified" needs some qualification, at least in some cases!

Kind Regards, John

 

[SUNRAY]

Methinks qualified sparks would not be confused.

Methinks any level of sparks, qualified or not, would not be confused. I can only think of one person who thinks he knows about elektwikewy who's likely to be confused on such a simple circuit.

 

[SUNRAY]

Having returned to this thread to get a picture about lighting rings for another thread it reminded me another little update was due.

The customer had been advised a time or two that the outbuilding for swimming pool, koi pool etc was due for updating, they indicated they preferred resolving the tripping problems first rather than relying on the rewire to fix the previously unidentified fault.

As of July they hadn't had any further problems other than another metal theft when they were getting shocks off the kitchen sink taps (flagstone floor). They had more work done in the outbuilding to refurb one room, I wasn't involved with the work so I don't have full details other than the room with the CU has been lined/decorated as a summer house (for want of a better description from me). The CU has been replaced with all RCBO and the SWA directly in the bottom using the same plastic gland and is now in the adjacent room, to the right where the RCD socket in my pic and the koi plant is located. AIUI most of the internal wiring is unchanged other than moved into the new CU and accessories for pools unchanged.
The external lighting & sockets and cabling (T&E clipped direct and tywrapped to catenary) has been replaced. For winston1 - I don't know if the lights are still on a ring circuit.

Details are not perfect but about as chatted over the phone 2 months ago.