House Not Earthed?

[zolarolla]

Have just started to do do some major renovation on our house and have removed a battered old box that was enclosing the service head. Revealed underneath was what appears to be a very Heath Robinson affair and even more worryingly the wiring seems to suggest that the house is not earthed ...

Location of service head:-

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• zolarolla
• 19 Nov 2008
• 1

Two CU angles on service head:-

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• zolarolla
• 19 Nov 2008
• 1

Untitled

• zolarolla
• 19 Nov 2008
• 1

I got in contact with the DNO (EDF) who sent a couple of guys around this morning who informed me that there was earth going up to the main service head block but not coming out to the fuse units to the right of the block. They then informed me that they were only responsible for the main block as the additional units would have been added by someone else when the meter was moved to the small cupboard that you can see in the bottom left hand side of the corridor in the first picture. They also bizarrely went on to say that in some older houses the main earth is linked to the gas mains and it is not necessarily the electricity suppliers responsibility to provide an earthed source.

I was under the impression that they would be responsible for everything up to and including the meter, but before I call EDF again I'd really appreciate any input from you guys out there.

Many thanks

zolarolla[/img]

 

[Chri5]

If you look on the main cable below the head there appears to be some sort of earth provided from the clamp round the mains cable and that extending to a bolt fix on the head to the lower LHS.

The DNO is not responsible for internal wiring, so earthing is the premises owners issue once on that side of the mains.

I'd suggest you get the DNO earth tested by a spark, if okay then he can supply a MET block with a 16mm cable between the MET and the service head earth point (large eyelet crimp over cable and put it under the same bolt the earth head is- suggestion ONLY).

From the MET you should have 10mm earth bonding cables to the gas and water main (within 600mm of the stop cocks), and a 16mm to a CU or in your instance cable suitably rated for the fuses you have.

Since they look well past the service level and there be further works down the circuits (earth checks, rewires or simply connection what hasn't been) I'd go for a full freshen up of the site- a rewire if necessary.

 

[bongos]

As I understand it (I spoke to a DNO about a similar matter this week) they are responsible for the supply up to your meter.

It does look like you have some kind of (undersized) earth in existence though.

 

[Spark123]

I can't help but think the whole thing is a bodge - the pyro only looks to be somewhere around 2.5mm? If you look at the pot on the end of the pyro there should be some numbers and letters on it i.e. 2H2.5 or 2L4. I'm thinking it doesn't really look large enough to supply a household.
Officially, only the DNO should work in this part of the equipment. It may be they will put the meter back on the board for you?
If they will then get them to terminate it into an isolator, then a household spark can connect a 60A or similar switch fuse to a sufficiently sized cable.
You are right in there doesn't appear to be any earth to the pyro supplying the meter.

 

[zolarolla]

Hi guys -- thanks very much for your quick replies.

Spark123 -- I'm a bit of an electrical novice so could you tell me what you mean by "pyro" and "pot". I've looked closely but can't seem to see any obvious number/letter combinations but I may be looking in the wrong place.

I'm still quite confused as to whether the DNO is responsible for everything before the meter i.e. the whole of the set up on the right hand wall or is it just the service head? As far as I'm aware I'm not allowed to touch anything until after the meter so someone must be responsible!! If I scream blue murder at them to come and sort it out would I be justified?

 

[Steve]

Its rare to see this. A long length of cable between the service head and meter. But yes, the cable is undersized, and I wouldnt think it was the work of a DNO. But I dont understand why the meter would have been moved from there to another location in the same room. I mean, fair play if you want your consumer unit lower down, but why the meter?

I'd ask the DNO if they could renew the supply - fit a new head and meter onto that board (or a new board if you wish to supply one pre cut - they wont)

And when they fit the new service head they may PME it too. The best option.

Then you need a spark to renew the supply to your consumer unit - the current setup is not ideal, and would need a 60 amp fuse to protect it at source (the DNO fuse may be 40-60 amps, but you cannot rely on this to protect your 10mm cable, you need your own fuse)

The best option is to run a 16 or 25mm² SWA cable to the CU position, or re-position the CU to the position above the door. It looks like the house is having a refurb, so its an ideal time to do this.

 

[Steve]

Pyro is that orange cable/pipe on the right. Its a type of cable that is resistant to fire, so often nicknamed pyro.

The pot is the bit on the end, which keep the mineral fibres in the cable and seals it from moisture.

 

[zolarolla]

Thanks Steve -- my electrical vocab is improving by the day.

I must admit that having the meter low down on the left is actually quite attractive to me now as to move it back to the top right hand side will create a bigger block once boxed in. This in turn will block out the window above the door even more. This of course is an aesthetic pov and I wouldn't want it to compromise safety if the run between service head and meter is too long. The diameter of the pyro is about 12.5mm.

If I ask the DNO to fit a new head and try and get them to PME it is this something that they will charge for is it their duty to do it as part of their service?

I'll certainly look into your advice regarding the supply to the consumer unit which I will have updated anyway.

 

[Spark123]

Look very carefully at the end of the pyro on the gland (the bit resting on the orange outer sheath) the and the pot (the bit where it turns to black wires) and see if there are any markings.
I'm just comparing them to what you have in the way of tails from the cutout to the henleys. It looks quite a bit smaller. Of course - we don't know what you have in the fuse holder (sealed brown holder in the middle) tho.
The people who should have done the moving of the meter are the DNO (leccy board) - I doubt they did this job
By all means have an electrician take a peep at it but don't be suprised if they take deep breaths!

 

[stem]

could you tell me what you mean by "pyro" ?

Pyro is actually an abbreviation of Pyrotenax Ltd, a company established in the 1930's to manufacture Mineral Insulated Copper Clad Cables. the name is used today for all MICC cables in a similar way that Hoover is used to describe all vacuum cleaners.

 

[Steve]

The people who should have done the moving of the meter are the DNO (leccy board) - I doubt they did this job

Odd. I agree, but the cutout and seperate fuse holder have been sealed.

 

[Spark123]

Maybe at a later date, if the meter has been changed etc.