"Milleniumaire" wrote in message
oups.com...
I live in a modern house that was built 7 years ago and we had a loft
extension built a couple of years ago. We are in the process of
re-decorating the loft and decided that chrome plated flat sockets and
light switches would complement the modern look we were trying to
achieve.

The fittings were ordered and received but I noticed that the light
switches have earth connectors and a label saying "This metal plate
must be earthed using the terminal marked earth".

On closer examination of my light switches, they don't appear to have
earth cables, just a live and switched live wire! The ceiling roses do
have earth connections but this earth isn't taken to the switches. I
know from experience that this isn't unusual and is the way that the
last three new houses I have lived in were wired.

Is it necessary for me to run an earth cable from the ceiling rose to
the light switch in order to fit these new metal boxes?

Could you also help me with the definition of a lug. Another label on
the switch says "If a 4 lug mounting box is used, the top & bottom lugs
must be bent fully back". Is the lug the thing in the mounting bot
that the screws screw into? I'm fairly sure it is but I'm not sure why
you would ever get 4 in a mounting box. Because the light switches are
fitted to plaster board walls in the loft, plastic mounting boxes have
been used which have the adjustable fixings i.e. they pull tight onto
the plaster board when the switch fitting is screwed on.

Thanks in advance for guidance on earthing the metal switches.


Wow!
Any exposed metalwork or metal-clad boxes (and linkage to their removable
metal panels fitted with: mains switches, sockets, spur outlets, etc) must
be bonded all the way to a good supply Earth.
It's Common sense, it's the electricity regulations, and it's the law. This
neglect could possibly nullify insurance claims, too.
You could unbodge it safely by just running green PVC-covered braided 1.5sq
mm copper wire from your reliable earth busbar (or from your ceiling rose
if it is truly earthed) -hidden hopefully- to the exposed metal
lighting-switch boxes and panels, and anything similar that is not yet
earthed,
or, to do it properly, you would have to rewire any such item with correct
gauges of twin and earth (may have either the old or the new colours) and
you will need 15A braided and green & yellow sleeving for the box-to-panel
linkages.
Before rewiring.... Make sure you have a good torch or secondary lighting,
and kill the area mains supply!!
Jim