No Earth cable in orginal ring circuit flex

[mapj1]

Wow, a PME installation WITH the proper warning labels intact, most unusual..
Seriously, in PME AKA TN-C-s (see the for reference section at the top of the forum, page 3.) neutral and earth are only combined in the supplier's cables, after the meter, earth and neutral are separated, and then go their separate ways about the house, never again to meet.. If its that new, the conduit will indeed form the earth conductor, so when working on the system do nothing that could affect the metallic continuity of conduit from one socket to the next, and if the conduit must be cut, then use earthing wire to bridge one section to the next (i.e. add a green/yellow wire following the route of the red and blacks if the tubing is not continuous.)
regards M.

 

[Beanzy]

What kind of property is it? Many 1930-50's apartment blocks had conduit systems. Are the conductors in a waxy cloth over rubber insulation? If so, due to the age of the installation, it would be wise to consider a rewire. The insulation on these often deteriorates badly near outlets, especially lighting outlets. If a rewire is done then it would be normal to pull through a separate earth conductor for each circuit rather than trying to rely on the conduit, which may have deteriorated at joints due to damp & rust etc over time. A quick way to tell if it's a conduit system is to go to the Fuse Box (or consumer unit if it's already been upgraded) and see if there are metal pipes leaving the enclosure, if so it'll be run in conduit.

If you find it is such a system then you should get someone in to do a Periodic Inspection Report, especially concentrating on issues of 'Earthing' & 'Bonding' as there'll be a lot of metalwork in that installation which could be at different potential to earth and to other metalwork. This can be dangerous if not properly bonded. If it's not a conduit system then you need to get someone in urgently as your final circuits will not trip the fuse if they are faulty, and may just be waiting to short to earth once a convenient body makes contact.

I'd say after you get an initial assessment of the system you should get someone in to do a proper check for you.

 

[ban-all-sheds]

What kind of property is it? Many 1930-50's apartment blocks had conduit systems.

The building was constructed in 1979.

 

[Damocles]

The PME does not have anything to do with how the house is wired after the CU. In the Uk it is customary to have a separate earth and neutral connection at least back to the main supply point within the house.

Other EU countries take a different view on whether this is necessary and interestingly the new building regulations allow you to wire to an alternative accepted EU standard. (or so I understand).

However your house has been wired with the intention of having an earth supplied by the metal trunking. As has been said, just make sure it is connected. Assuming it was competently done in the first place then there is no need to panic and no need to asume it is on its last legs.

 

[Screwi]

Im quite concerned here, your giving advice to a guy who quite clearly isnt competent to do the job.

And from what ive seen, based on this, I havent read that any of you have told him to remove the power to the ring main by either removing fuse or switching of MCB or by turning the main CU switch off, and yet a number of you are telling him to check earth etc etc, which involves removing the socket from backplate with live wires contained within!

Im not being nasty, but some people will over look the obvious and work live!

 

[ban-all-sheds]

And from what ive seen, based on this, I havent read that any of you have told him to remove the power to the ring main by either removing fuse or switching of MCB or by turning the main CU switch off, and yet a number of you are telling him to check earth etc etc, which involves removing the socket from backplate with live wires contained within!

He's already been doing that, before he came here:

Inspecting sockets in my flat, I notice that the original flex is only two cables ...I'm adding some spurs

Im not being nasty, but some people will over look the obvious and work live!

They might, but this wasn't a case of advising someone who hadn't had sockets off already...

 

[ban-all-sheds]

3) You appear to be wiring new sockets with 25mm flex, not 2.5mm cable.

Per my answer above, I have actually purchased Pirelli 2.5mm(squared) solid twin & earth cable.

Surely it doesn't have a sleeved earth?

 

[Damocles]

Screwi, I always give advice which I believe is to the point being asked. Sometimes I might point out a danger if I think it has been overlooked.

I do not believe in explaining to everyone that there are two shiny metal things - one either side of the square white plastic plate. That you should get a tool called a srewdriver. This has a flat squared end about 3mm by 0.5. what you do is put the sharp end of the screwdriver into the slot across the top of the shiny metal thing. Then you turn the screwdriver anticlockwise. (which is the opposite way to which the hands turn on a clock)......

If people ask for safety advice I will give it. If they ask for advice on how a socket should be wired i will give that instead. I have never pretended that any suggestions I make are a complete explanation of anything. No one gives a complete answer in a post.

 

[jgreer]

Since creating this thread, I got out my ohm meter and checked the earth connection of every socket in the house for resistance to pipes, conduits etc. All showed no resistance.

After installing my new steel bath, I connected the earth to it as well (like the previous bath) and tested the bath. This was fine too.

Thanks for your help, everyone.