TN-C-S Distrubution Fault Symptoms?

[ban-all-sheds]

I did disconnected from the main earthing bar in the MCU

but there is a second earthing bond to a second MCU so to speak fitted for a previous Economy7 system, i didnt disconnect that.

And does that provide an earth for your sockets, your lights, your cooker, your shower, your immersion heater etc?

I had reconnect the main earth bond from the PME to the MCU 24 hours later, the house felt considerable worse.

So you deliberately ran your house for 24 hours with no earth?

We currently have the downstairs ring main off, as when its on we feel considerably worse than when its off.

Then get some tinfoil hats.
Or build a big pyramid over the house.
Or sprinkle crystals around.
Or sacrifice a goat.
Or run widdershins 3 times.

Anything, in fact, rather than fiddle with your electrics. Do you have any idea of how much worse somebody could have felt as a result of your mad experiment?

based on the information displayed in the new on-site guide

Maybe you can sell it on eBay.

Its a family home with two generations of family currently resident, and we all feel noticeable difference, and we are not paranoid bunch.

I expect somewhere you can find two generations in the same house who genuinely believe that if they replace the power cords on their hi-fi with very expensive ones which at one time were made really cold then it will sound better.

since we already feel horrid in the same areas the meter detects strange readings, there is more evidence than just a odd meter.

Where is the real, solid, scientific evidence from proper studies, statistically significant double-blind trials etc?

This is not mind over matter

And did you know that the US government blew up the WTC with thermite bombs?

noticeable physical differences are felt went entering or leaving the home, regardless if we think about it or not.

I'm sure they are.

 

[ElectricsRanger]

I understand the point your making John, but in the case it looks like it could be making more of difference than expected.

Also i don;t think you should confuse extraneous-conductive-part as a need to earth the main supply cable from the three phase system, the regulations show that a TN-C-S installation should not be earthed to the supply cable, but to the PEN. Its right at the back of the cupboard, its not like it a metal sink.

I do respect your input on this matter John, so im still considering all the points at the moment.

I wanted to get an electrical contractors to check the installation, but they are either to busy, or they think its to much hassel. I especially wanted them to confirm if i need to bring the electrical grid guys out and check my supply installation. Its good to share, but i don't think i want to share my main earth with my neighbours.

Im going to purchase a clamp meter as well, and test the current flowing through the main earth cables.

Thank you everyone for you help.
Ill report back later.

 

[ban-all-sheds]

I understand the point your making John, but in the case it looks like it could be making more of difference than expected.

How?

Also i don;t think you should confuse extraneous-conductive-part as a need to earth the main supply cable from the three phase system,

I don't think that you should not regard a metal sheath, in contact with the ground, and entering the house, as an e-c-p.

the regulations show that a TN-C-S installation should not be earthed to the supply cable, but to the PEN

And that PEN conductor is where, exactly?

I wanted to get an electrical contractors to check the installation, but they are either to busy, or they think its to much hassel.

There is a 3rd possibility....

Its good to share, but i don't think i want to share my main earth with my neighbours.

What do you mean by that?

It's called "earth" for a reason. You do realise that that the only way not to share it with other people is to find another one to live on where there are no other people?

Im going to purchase a clamp meter as well, and test the current flowing through the main earth cables.

While you wait for that, read this:

In the area of biological effects and medical applications of non-ionizing radiation approximately 25,000 articles have been published over the past 30 years. Despite the feeling of some people that more research needs to be done, scientific knowledge in this area is now more extensive than for most chemicals. Based on a recent in-depth review of the scientific literature, the WHO concluded that current evidence does not confirm the existence of any health consequences from exposure to low level electromagnetic fields ... Some members of the public have attributed a diffuse collection of symptoms to low levels of exposure to electromagnetic fields at home. Reported symptoms include headaches, anxiety, suicide and depression, nausea, fatigue and loss of libido. To date, scientific evidence does not support a link between these symptoms and exposure to electromagnetic fields ... There is little scientific evidence to support the idea of electromagnetic hypersensitivity. Recent Scandinavian studies found that individuals do not show consistent reactions under properly controlled conditions of electromagnetic field exposure. Nor is there any accepted biological mechanism to explain hypersensitivity ...

 

[EFLImpudence]

Also i don;t think you should confuse extraneous-conductive-part as a need to earth the main supply cable from the three phase system, the regulations show that a TN-C-S installation should not be earthed to the supply cable, but to the PEN.

Im going to purchase a clamp meter as well, and test the current flowing through the main earth cables.

There is only one.

It is called THE earthing conductor.

 

[ElectricsRanger]

Agreeded i didn't assume the cables were there, and that i was hundred percent reliable, but it shows some good signs as being way more reliable than my hand or six sense. I also took up the floor board and visually inspected the installation, and the cables are where it detected them. I conclude something is wrong with the ring main, because the field should not be detected a meter distance below or either side of the cables, and the meter has shown to be reliable measuring all the other circuits in the house. There is no foil back plaster boards in this area, no metal joists or other cables of any type. The meter even detects the earth cables with an amber when the ring is off. The meter is also not a £30 its a £150 meter, and its better than i expected, but i agree with you, its going to have a tolerance of accuracy..

No... I didn't completely disconnect the earth, it was still connected by a second MCU, not that i wanted it to be. I also checked my earth bonding to the water main from the main MCU, to be sure i had some kind of earth. I was trying to troubleshoot the issue, and took precautions. Im also trying to solve the problem, not moan about it.

Im in the process of assembling proper facts. You can speculate, its not your problem at the end of the day.

 

[PBC_1966]

Perhaps - but a common reason for converting TN-S to TN-C-S is because the sheath ('TN-S earth') has broken, or at least deteriorated, somewhere.

Agreed. And whether the sheath on the particular service run from the main to the individual house is still intact or not, the link should still be there. If the sheath is intact, then it will simply carry some of the neutral current. If it isn't, or at some future point deteriorates so that it isn't, then the link at the cut-out ensures that the section of sheath from the there back to the bad area remains earthed.

Also i don;t think you should confuse extraneous-conductive-part as a need to earth the main supply cable from the three phase system, the regulations show that a TN-C-S installation should not be earthed to the supply cable, but to the PEN.

Your installation is earthed to the PEN. It's just that the sheath of your old supply cable is also connected to the PEN, certainly at your end, probably at both ends.

As time goes on and old lead-sheathed main cables are replaced with cables which employ a combined neutral/earth, TN-S is gradually disappearing. In some cases even though you may look at the old service within a home and think that it's TN-S, in reality it may not be because the DNO has replaced mains and if you could look at where your old service cable has been joined to the new main, the neutral and sheath are just both connected directly to the new PEN.

 

[ElectricsRanger]

There is only one.

If you look at the photo you can see two large main earth cables disapearing out the top of the image, the right earth goes to my MCU earth terminal bar. The left earth travels to a second MCU for a previous Economy 7. Im thinking i may measure the current flowing through them.

 

[PBC_1966]

I also took up the floor board and visually inspected the installation, and the cables are where it detected them. I conclude something is wrong with the ring main, because the field should not be detected a meter distance below or either side of the cables, and the meter has shown to be reliable measuring all the other circuits in the house.

If you believe that there might be some problem with the ring final circuit, then why not carry out the usual range of comprehensive tests on it? Disconnect at the board, check loop resistance of L & N, test insulation resistance L-N and to earth etc.

 

[ban-all-sheds]

No... I didn't completely disconnect the earth, it was still connected by a second MCU

It was connected to another consumer unit (MCU).

And does that CU supply sockets, lighting and appliances in your house, or did you remove the earth connection for all of those for a period of 24 hours?

I also checked my earth bonding to the water main from the main MCU

That is bonding of the incoming water supply, not an earth for your installation.

to be sure i had some kind of earth.

You measured what your fiddling had done to your Zs, did you?

I was trying to troubleshoot the issue, and took precautions.

Such as moving out or turning off the main switch until the earth connection was re-instated?

Im in the process of assembling proper facts.

Don't be ridiculous.

 

[JohnW2]

Also i don;t think you should confuse extraneous-conductive-part as a need to earth the main supply cable from the three phase system, the regulations show that a TN-C-S installation should not be earthed to the supply cable, but to the PEN.

Quite so!

Kind Regards, John

 

[ElectricsRanger]

Agreed. And whether the sheath on the particular service run from the main to the individual house is still intact or not, the link should still be there. If the sheath is intact, then it will simply carry some of the neutral current. If it isn't, or at some future point deteriorates so that it isn't, then the link at the cut-out ensures that the section of sheath from the there back to the bad area remains earthed.


Your installation is earthed to the PEN. It's just that the sheath of your old supply cable is also connected to the PEN, certainly at your end, probably at both ends.

As time goes on and old lead-sheathed main cables are replaced with cables which employ a combined neutral/earth, TN-S is gradually disappearing. In some cases even though you may look at the old service within a home and think that it's TN-S, in reality it may not be because the DNO has replaced mains and if you could look at where your old service cable has been joined to the new main, the neutral and sheath are just both connected directly to the new PEN.

I don't think i have a TN-S installation now, i can see its on the way to being a TN-C-S. What im concerned about it the amount of current that is flowing through my installation possibly though my earth cables, when the main breaker is off, and the how the installation seems to perform when its under load.

Just to give you an idea of the cable age, its installed in a house built in 1955 to 1960.

The installation needs a check up, and needs certifying. Who do i call, do i call E-On?

Thanks.

 

[PBC_1966]

Also i don;t think you should confuse extraneous-conductive-part as a need to earth the main supply cable from the three phase system, the regulations show that a TN-C-S installation should not be earthed to the supply cable, but to the PEN.

Quite so!

I took the comment to imply "should not be earthed to the sheath of the supply cable."

 

[JohnD]

i can see its on the way to being a TN-C-S.

On the way? On the way??

 

[JohnW2]

If the sheath is intact, then it will simply carry some of the neutral current. If it isn't, or at some future point deteriorates so that it isn't, then the link at the cut-out ensures that the section of sheath from the there back to the bad area remains earthed.

Indeed. However, I think that the OP was suggesting that the sheath should be 'disconnected' - in which case, as I said, it would become a (potential) extraneous-c-p which would have to be bonded anywhere - so essentially 'back to square one' in terms of 'what was connected to what'!!

Kind Regards, John

 

[JohnW2]

I took the comment to imply "should not be earthed to the sheath of the supply cable."

If the installation were 'earthed to the sheath of the supply cable' (rather than to the PEN conductor), then it would not be TN-C-S - so the OP's comment makes no real sense!

If the supply cable sheath (or, indeed, a customer's TT electrode) provides an adequate earth, there is no obligation to use a TN-C-S earth, even when one is available.

Kind Regards, John