Where is the house's earth

[securespark]

PME is great, but we're not sure you have it!!

As John suggested, post some pictures of your electrical intake & CU(s).

Have a butcher's outside and see if you have an earth electrode sticking out of the ground near the intake.

If you have, post a piccy of that, too.

 

[ban-all-sheds]

underground water and heating (and gas?) pipes that provide some earthing, or a lot of earthing

They don't.

If they are metallic, and enter the house, they are extraneous-conductive-parts, and they require bonding.

In that case if the neutral was interrupted somewhere outside the house, would all those earthing points provide an alternative neutral ?

An open circuit PEN is pretty rare - even accounting for such things as CONSAC cable with an aluminium CNE

An open circuit PEN in the most unfavourable position is even more rare

An open circuit PEN in the most unfavourable position and not shunted by a whole load of surrounding properties is even more rare, still

 

[stillp]

it's a joke, as is Mr Cockburn and his book

Hardly a joke BAS, more a dangerous charlatan. I thought Amazon had stopped advertising his ramblings, but obviously they've decided that a little more profit outweighs a few more dangerous electrical installations.

 

[ban-all-sheds]

They've always done that.

I expect they are also selling US electrical installation books, and we all know that they "sell" dangerous and/or counterfeit electrical items.

They do all these things because they care more about profits than they do about people's lives, morality, decency, honesty, social responsibility and so on.

 

[Risteard]

Protective multiple earthing sounds great.

Actually TN-C-S (usually PME) is arguably the worst earthing arrangement available.

 

[Risteard]

PME is great

Most would disagree.

 

[bernardgreen]

PME is great,

It is, until there is a fault in the local network such as theft of copper from the network. The criminals go for the Neutral as there is far less risk of electrocution when cutting the Neutral.

In 99% of installations it is better than earthing using a ground rod as ground rods cannot carry enought fault current to blow fuses or operate MCBs, hence they require an RCD to protect the installation. They can also dry out and become in-effective in dry weather or in poor ground.

Historically when the water supply network was all metal pipes the water pipe to a house did provide a reliable Earth. Plastic water pipes meant an alternative was needed without the cost of adding an Earth wire to all electrical supply network cables.

 

[andy_g]

My house is PME. Can I make things better/safer by earthing into the ground here and there? Is there a disadvantage in doing this?

 

[John D v2.0]

My house is PME. Can I make things better/safer by earthing into the ground here and there? Is there a disadvantage in doing this?

The best thing you can do is remove the bonding from your water, fit an insulation joint to your gas supply, and only use class II appliances.
Earthing here and there won't do anything useful as far as I can tell, as the resistance would be too high to make any difference. The only use of a normal rod is to provide a reference point for tripping an RCD. But the risk with pme described above Is not taken away even if all the protective devices in you're house tripped.
Why are you so concerned?

 

[Iggifer]

I couldn't even tell you what earthing method I have in my (rented) flat.

I've checked a couple of socket outlet Zs readings and that's good enough for me. So long as I have an earth, it could come from a piece of wet string tied to the base of a lamppost for all I care.

 

[EFLImpudence]

What happens in TT installations when the neutral is lost/stolen?

 

[endecotp]

My house is PME. Can I make things better/safer by earthing into the ground here and there? Is there a disadvantage in doing this?

In another thread you mentioned that you don't have RCDs. Fitting them would be by far the most useful thing you could do to make your electrical system safer.

Regarding adding earth rods to a PME system - it's quite possible that there is some subtle disadvantage that this could introduce, such as high earth currents theough too-thin earth wires causing heating. Don't do it.

 

[John D v2.0]

What happens in TT installations when the neutral is lost/stolen?

Is it a trick question?
If so, I suppose you're suggesting he could disconnect his bonding and CU from the supplier's earth altogether and make a TT system, good point, and which would indeed be safer if the neutral is lost (but less safe if the RCD fails, so pick your risk carefully!)

 

[EFLImpudence]

It was rhetorical.

It was suggested that electrodes be connected to a TNC-S installation in case the neutral is lost.

 

[Risteard]

It was rhetorical.

It was suggested that electrodes be connected to a TNC-S installation in case the neutral is lost.

Many (most?) countries require earth electrodes in TN-C-S systems. In fact it looks like this may be addressed by the 18th Edition.