In article ,
Steven Briggs writes:
In message , Mike Hall
writes
We've just bought a bathroom wall light, (from Habitat), that claims
to be Class 2 and specifically says that no earth should be attached.
Looking inside I can't see how on earth (pun intended!) it can be
double insulated, and I believe it will be much safer with an attached
earth. The case of the light is painted metal, (aluminium), and
inside there are mains votage wires. i.e. The separation between the
mains voltage and the aluminium consists of the brown single layer of
sheath around the cable and then the paint on the metalwork. Does
paint really class as a layer of insulation for these purposes?

Generally paint & enamels aren't counted for safety grade insulation.
I'm not totally familiar with the lighting equipment standards, but from
your description is doesn't sound like the product qualifies as double
insulated. If the insulated & sheathed mains wiring terminated inside
some sort of plastic housing (i.e. a fully enclosed lamp base) within an
otherwise metal case then OK, but if you're saying there are single
insulated wires possibly in contact with the metal case, that sounds
dodgy to me.

I don't have the standards, but it was described on a course I did
a few years ago. IIRC, two layers of insulation are required. One
can be air, but something needs to ensure a suitable gap is maintained
in this case. Unsheathed insulated conductors which can come into
contact with exposed metalwork would not count as double insulated.
Are you sure additional sleeving wasn't provided to slide over the
singles (not that I'm sure if this makes any difference)?

--
Andrew Gabriel