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The earths on lighting circuits here in Ireland wern't manditory until relatively recently, I'm not 100% sure when they came into force. However, this house was originally wired in 1971 and has none! We had a horrible retrofitting job, particuarly down stairs where there was no access from behind the ceilings. Only a couple of old metal fittings upstairs and the bathroom lights were earthed.

I think the logic in the old days was that people would be quite happy with plastic fittings and if you wanted a metal fitting it would be installed by an electrician anyway, thus properly earthed. They didn't seem to count on the DIY jobs done everywhere.

There are certainly plenty of metal light fittings around that arn't earthed.

More worrying is when people install brass / metal switch plates in 1960s/70s wired houses and don't bother hooking up an earth.

I had one some time ago in which the light fitting had been replaced with a combo fan/light, and the switches in the living room had been changed to brass types. The report was of "slight tingles" when touching the plates sometimes.

All the earth terminals on the fan and switches had been carefully interconnected
with new T&E and 3c+E cable, but the feed was then spliced to the original non-earthed lighting circuit, the earth just left disconnected.

Given the circumstances, it would actually have been better to have left all the earth wires diconnected to avoid the combined capacitance and to avoid the possibility of "exporting" an earth fault from one point to another.

I have to admit ungrounded stuff doesn't bother me that much as long as there aren't any Schuko sockets without ground involved. Having grown up with a truckload of old ungrounded wiring and class 0 appliances with old bakelite plugs it just doesn't seem unusual.

To be fair, the old light circuits with no earths were installed before homeowners were allowed to change fittings themselves ( De-regulation ).

Back then it was safe to assume that a metal light would be installed by an electrician and he would install the appropriate earth wire too.

Interesting that here in NZ we "de-regulated" a few years before we made RCDs mandatory.

Hmmm.... Anyone trying to tell somebody that he wasn't allowed to change a light fitting in his own home around here would no doubt have been told exactly where to go in no uncertain terms.

Its those damn aluminium ladders. Before they came along you didn't need to earth metal light fittings because you were insulated from earth by the wooden ladder.

Paul, likewise here, if you told someone that they couldn't fit their own light fittings you'd have uproar!

Briselec, you can put any outlet you like on a 1mm cable. The protection on the circuit is what matters. 1mm cable de-rates heavily as soon as it hits thermal insulation ( batts) etc. A 10A breaker should only be used on short 1mm TPS runs where there is no thermal insulation involved.

True but I tend to ignore that fact and still work to the rules in the previous edition of the wiring rules regarding GPOs.

I've never understood why they have a table of minimum cable size and then say "but you can use smaller sizes". That doesn't make sense to me.



1mm is rated at 10A when partially surrounded in thermal insulation

Who still uses 1mm2?.
I thought that went out in 1990.
I haven't used it in years, apart from control relay panel stuff.
I most certainly wouldn't install it in anyone's house.
Besides it's too hard to keep flat during clipping.
Down here locally 1.5mm2 is the minimum size.
If you buy 1mm2 here you are a cheap-skate.
Each to thier own though I suppose.

{Message edited for grammatical errors}

[This message has been edited by Trumpy (edited 06-01-2006).]