Earthing

[londoneye]

Hi

Can someone please advise, if you use all plastic piping (no copper at all) is it necessary to earth the sinks/taps etc.

The kitchen sink is stainless steel, bathrooms are all ceramic.

Hope this makes sense !

[Pierre ZFP]

Firstly let me say that I have no knowledge of this at all but intuitively I would say yes it should be earthed only because the water in the pipes could conduct electricity.  I'm sure those who really know will be along shortly

[Quillan]

No you don't according to UK information.

I never knew this so I simply typed the following in to google

do you need to earth metal baths with plastic tubing

which came back with the following at the top of the list.

http://www.plasticpipesgroup.com/pdfs/earthbonding.pdf

Here is a more technical link BUT I must stress that this information is for UK installations which are quite different.

http://www.ultimatehandyman.co.uk/EarthingPlasticPipes.pdf

To be double safe I would bond the taps and anything else that may be metal that you can touch in bathrooms that have water in or nearby, thats just me and it would be for my own personal peace of mind regardless. You might try asking a French plumber or Electrician.

[londoneye]

Well, small update - and sorry I never got back to thank those who replied.

Diagnostic man has now checked our electrics (and energy rating (oh dear !)) and no problems with the earthing (or lack of) of the individual appliances.

However, our external earth rating (sorry probably not the correct term) was not sufficient. We actually have four earth spikes on the property (one for each building) and none were acceptable. Diagnostics man suggested joining them all up and connecting them all to some kind of earthing grid buried in ground (no idea what he is talking about). In fairness I should say that he also recommended discussing with an electrician.

Has anyone any suggestions (apart from discuss with electrician, because if it is something we can put right ourselves then we would prefer to do this).

Anyone with experience of this? The readings were around 1000 (should be less than 500 apparently).

[Badger LX]

I'm not sure what your chap was reading but the resistance of your main earthing system(s) must be below 100 Ohms, if you have a main "disjoncteur d'abonné" of 500mA (which is the standard these days).

If this is the case for all your earth spikes then the suggestion of linking them all up is a good one as you would use bare 25mm² copper wire to perform the task which gives you a lot more contact with earth than a few extra spikes would achieve. However, this should only be done if all the buildings are fed from the same mains supply/meter.

[Alan Zoff]

Seems to be common in rural France to have woefully inadquate earthing.

When I bought our house, there was a skinny bit of earth wire which ran from the fuse box to the concrete path outside the back-door. It went a couple of centimetres into the concrete, and that was it. The local qualified electrician seemed to consider it adequate, though, when he wired up the cellar for the previous (French) owner to house the washing machine, boiler, etc. and simply connected the earths to the ground terminal on the old fuse box.

The uselessness of the earthing point was of little relevance to the rest of the house as it was all either 2 wire only or the earth wires were not connected to anything. This included a workshop full of electrical tools. No sign of any cross-bonding anywhere in the property.

The electrician, by the way, has moved out of the area and I believe now runs a B&B and sells second-hand clothes.

[Northender]

[quote user="Alan Zoff"]Seems to be common in rural France to have woefully inadquate earthing. When I bought our house, there was a skinny bit of earth wire which ran from the fuse box to the concrete path outside the back-door. It went a couple of centimetres into the concrete, and that was it. The local qualified electrician seemed to consider it adequate, though, when he wired up the cellar for the previous (French) owner to house the washing machine, boiler, etc. and simply connected the earths to the ground terminal on the old fuse box. The uselessness of the earthing point was of little relevance to the rest of the house as it was all either 2 wire only or the earth wires were not connected to anything. This included a workshop full of electrical tools. No sign of any cross-bonding anywhere in the property. The electrician, by the way, has moved out of the area and I believe now runs a B&B and sells second-hand clothes.[/quote]

 

Probably  belonging to all his customers he managed to kill during his past career.

[pachapapa]

The french reasoning is as follows.  A voltage greater than 50 V at frequency 50 Hz is dangerous. The EDF connection includes a 500 mA differential breaker. Applying Ohms Law the resistance will be 50 divided 0.5 that is 100 ohms.

So just remember 50 volts, 500 mA and 100 ohms.[:-))]

[Théière]

[quote user="pachapapa"]

The french reasoning is as follows.  A voltage greater than 50 V at frequency 50 Hz is dangerous. The EDF connection includes a 500 mA differential breaker. Applying Ohms Law the resistance will be 50 divided 0.5 that is 100 ohms.

So just remember 50 volts, 500 mA and 100 ohms.[:-))]

[/quote]

Oh and you cannot get electrocuted on any other floor but the ground floor so earthed sockets are not required?

[pachapapa]

[quote user="Théière"][quote user="pachapapa"]

The french reasoning is as follows.  A voltage greater than 50 V at frequency 50 Hz is dangerous. The EDF connection includes a 500 mA differential breaker. Applying Ohms Law the resistance will be 50 divided 0.5 that is 100 ohms.

So just remember 50 volts, 500 mA and 100 ohms.[:-))]

[/quote]

Oh and you cannot get electrocuted on any other floor but the ground floor so earthed sockets are not required?

[/quote]

Oh so drôle tea-pot! Your proposition intuitively works in english for the ground floor; in french with a "rez de chausée" it is not so intuitive.

A mini table for earth resistance requirements;

650mA/77 ohms
500mA/100 ohms
300mA/167 ohms
100mA/500 ohms
30mA/1666 ohms
The NF C 15-100 now requires 30mA differentiels.

Dont get me started on the Chilean earthing regulations for earthing of ewplosive magazines in the dryness of the Atacama desert.

A big laugh this week, I had a read of the new book by someone called Malcomb, a tôme of 80 pages no less, on french electro-technology for Brits; in particular the portion about the difference between 13 Amp fuses in British plugs and power sockets in france had me rolling on the floor crying with mirth.

Sort of booklet that needs to be hung by the toilet roll in the loo..gentle laughing helps the f(ae)ces along on their fundamental voyage.

If I have time later I'll edit the ae. 

[Badger LX]

Whilst I don't dispute the values you state for earth resistance they are a bit of a red herring......

The earth resistance requirement is a product of the value of the disjoncteur de branchement & as I've yet to find one below 500mA fitted by ERDF, 100 Ohms is the effective maximum value allowed.

As a footnote, as well as requiring all circuits to be protected by 30mA inter diffs  NF C 15-100 also forbids the fitting of unearthed sockets. The only exception to that is if they are sockets supplied via an isolating transformer.

[Chancer]

[quote user="pachapapa"]

The french reasoning is as follows.  A voltage greater than 50 V at frequency 50 Hz is dangerous. The EDF connection includes a 500 mA differential breaker. Applying Ohms Law the resistance will be 50 divided 0.5 that is 100 ohms.

So just remember 50 volts, 500 mA and 100 ohms.[:-))]

[/quote]

And that I believe is the reasoning behind one of the more bizaare features of French electrical normes, one can have an electrical socket beside a kitchen sink (but not above) but for the obligatory telephone socket there has to be a seperation of IIRC 600mm [:-))] , forgive me if thats not 100% right as my books are on the chantier.

The only sensible explanation I have had to explain this, other than the statutory "c'est comme ça!" is that the telephone line has a potential of 50 volts but is not RCD protected.

So in  French property that conforms to the normes the telephone socket is indeed more dangerous than the whole electrical installation [geek]

[pachapapa]

[quote user="Chancer"][quote user="pachapapa"]

The french reasoning is as follows.  A voltage greater than 50 V at frequency 50 Hz is dangerous. The EDF connection includes a 500 mA differential breaker. Applying Ohms Law the resistance will be 50 divided 0.5 that is 100 ohms.

So just remember 50 volts, 500 mA and 100 ohms.[:-))]

[/quote]

And that I believe is the reasoning behind one of the more bizaare features of French electrical normes, one can have an electrical socket beside a kitchen sink (but not above) but for the obligatory telephone socket there has to be a seperation of IIRC 600mm [:-))] , forgive me if thats not 100% right as my books are on the chantier.

The only sensible explanation I have had to explain this, other than the statutory "c'est comme ça!" is that the telephone line has a potential of 50 volts but is not RCD protected.

So in  French property that conforms to the normes the telephone socket is indeed more dangerous than the whole electrical installation [geek]

[/quote]

The telephone is a nominal 48 v DC, possibly 100 v when ringing. Not likely to harm you.  Try it on your tongue! Oh Dawg now I'll have the PC brigade on my back again.

Not sure about the heights of your plugs, but there is a special part of NF C 15-100 for dwellings for the disabled. I have heard of but never seen Brits who have not read the text properly and have installed in accordance with "for the disabled". I expect they have wide parking spaces as well. 

[pachapapa]

[quote user="Badger LX"]Whilst I don't dispute the values you state for earth resistance they are a bit of a red herring......
The earth resistance requirement is a product of the value of the disjoncteur de branchement & as I've yet to find one below 500mA fitted by ERDF, 100 Ohms is the effective maximum value allowed.

As a footnote, as well as requiring all circuits to be protected by 30mA inter diffs  NF C 15-100 also forbids the fitting of unearthed sockets. The only exception to that is if they are sockets supplied via an isolating transformer.
[/quote]

I am sure that 500 mA is the standard, got one on the wall. I am with SEOLIS which originally SIEDS. SIEDS dates from early in the 20th century, Syndicat Installation Eléctricité Deux-Sèvres, originally DC and then tri-phase AC, still some 3 phase in the remoter rural areas. I believe that 650 mA was used prior to 500 mA but never less.

The wiring in my house built in the 17th century is certainly pre The Great War; as long as I can still get 5A, 7A, 10A, 15A fuse wire on a card from GE Vynckier I shall be alright.

[IMG]http://etab.ac-orleans-tours.fr/clg-hubert-fillay-bracieux/physique/3/electricite3/celec31_fichiers/images.jpg[/IMG]

[pachapapa]

Familiar porcelain bits like found in rural france. Check section B8.

http://www.diag-agences.com/UpFichier/ELEC/indexelect.pdf