Earthing when using leccy hookup?

[dublicious]

Lo Guys,

Had a situation the other night round my inlaws where we wanted to hookup up our westy camper to the mains for a bit of heat. Father inlaw asked us would the camper be OK on a house that is grounded on a PME system rather than a T & T system commonly used on campsites? I didn't have a answer and got very cold that night. So I can chuck it back in his face does anyone know an answer, apart from feck off, that I can give him tomorrow as sleeping in camper again?

I don't know how internal wiring works but all I can say its a proper hookup factory fitted jobby.

Take care and have a great new year,

J

[andisnewsyncro]

Never crossed my mind in all honesty, we keep ours hooked up at home and we have a PME fitted, at our electrician's suggestion, when he put in all the wiring for the sheds etc.

All I can say is that the PME has been in longer than we've had the van and so far everything's been ok. I was told that the PME just reacts quicker to shut down if there's any problem, short etc. in the system.

Be interesting to follow this thread and see what others have to say about it. Always good to find out what I should be doing as opposed to carrying on regardless in my own littele way

Andi

[Mr Bean]

Why on earth (Clever pun) didn't you just plug it in and see. Surely the worse it could do is trip simply requiring the press of a button and an apology. I was plugged into my daughters garden shed over Xmas but could only use the low setting on the fan heater as it was limited to 5A. I should know this but PME? Sounds like the posh name for something quite ordinary. Surely they must all work on the residual current principle nowadays. Some one please explain.

[Mocki]

as i understand it PME(protective multiple earthing) is A TN-C-S system, which has the supply
neutral conductor of a distribution main connected with earth at source and at intervals along its run.As oposed to a
A TN-S system, which, has the neutral of the source of energy connected with earth at one point only, at or as near as is reasonably practicable to the source, and the consumer's earthing terminal is typically connected to the metallic sheath or armour of the distributor's service cable. With this arrangement the distributor's neutral conductor is also used to return earth fault currents arising in the consumer's installation safely to the source. To achieve this, the distributor will provide a consumer's earthing terminal which is linked to the incoming neutral conductor.

E D I T:
i just looked this up, and it would appear that

Whilst PME systems provide an effective and reliable earth connection
precautions need to be taken when dealing with special locations. Regulation 9(4) of the Electricity Safety, Quality and Continuity Regulations does not allow the combined neutral and protective conductor to be connected electrically to any metalwork in a caravan or boat. This prevents PME terminals being used for caravans or boat mooring supplies, although they may be used for fixed premises on the sites, such as the site owner's living
premises and any bars or shops, etc

[T'Onion]

Failing all that , take a big extension lead and plug that in , serves the tight git right , whack it up full all night , get his meter spinning

if it get too hot open the slider

[dublicious]

Cheers guys, we didn't want to try as he went off on one, pissed rant, as he was worried to could electrocute us when touch the bus ! Blimey Steve I am going to have to re-read yours a few times with a clear head

Thanks again

[dublicious]

Lol, that would royally feck him off But I couldn't or could I

Failing all that , take a big extension lead and plug that in , serves the tight git right , whack it up full all night , get his meter spinning

if it get too hot open the slider

[VWCamperfan]

I give in! I have tried three times now to reply to this and each time it looses my reply... Stoopid, stoopid, stoopid!
Anyway, just in case it works, plug in. (I cant be asked with the explanation again!)
Its perfectly safe, just two different ways the earths are created.
If there was a problem everyone would be trying to figure out if thier lawnmower could be pluged in safely because thier supply is different to thier neighbours up the road!

[VWCamperfan]

Ooh, Yippee!

Ps, forgot to add, now I can post again, The only problem with a PME system is if for some reason the neutral back to the power station became damaged and broken and couldnt return the power. The 'earth' connection then becomes potentially live, which is why everything in a house is electrically bonded to create a same polarity environment so avoiding shock or electrocution. Your van wont be bonded to this system so if something did go horribly wrong your van could become live and the ground outside would be earth. If you touched the two at the same time, you could become a bit hotter than you wanted!
As said, there does have to be a major bodge somewhere for this to happen but as Steve said, if you don't have the earth connected to anything metal on the van, you will be ok.

[DiscoDave]

i've had a right do with a bloke on another forum about this. he says you can't plug your van in at home if you have a PME supply! nearly every house in the UK has a PME supply. as stated it has one live conductor and one neutral conductor, the main earth for the installation is achieved by "tagging" on to the neutral at the mains cut out. from the meter on there is an earth with every live and neutral conductor.

effectively the PME part stops at the cut out because from there on there is an earth. you plug your van in to a normal socket in the house, it has an earth, the electrical system in your van is in effect an appliance, it has it's own safety measures (rcd and trips) and can be dissconected by means of a plug.

the bit about not supplying a caravan/van etc with PME means you are not allowed to run a PME sub main to a mobile unit, this means you have to have an earth from the main installation into the van/caravan etc.


in summary it is perfectly safe! however it is well worth getting a plug in tester, this will confirm that you have all the conductors present and that they are connected the right way so proving that you have an earth