On 18 Jan, 17:50, Unclebill wrote:
I have bought a new ceiling light for my wifes latest project, an Art
Deco living room ! On removing the existing fitting I found that there
are only two cables both of which are coloured red!
As the new fitting has a step down transformer I assume it will be
necessary to wire it correctly i.e. Live to live and neutral to neutral
and somehow fit an earth (the two red cables are contained in an iron
tube conduit).
How do I find out which is live and which is neutral without any test
equipment??

--
Unclebill

Come on guys - not very intelligent answers. Try thinking first.

The answer is that a transformer is totally insensitive to which way
it is connected - it is after all just a floating coil, (or strictly a
pair of coils - primary and secondary). So it doesn't matter which
way it is wired.

As far as the earthing is concerned, if there is no earth tag on the
fitting, then it is safe to assume that any metal parts are isolated
from the fitting and that a double fault would be required to make the
fitting live.

If on the other hand there is an expectation that the fitting should
be earthed, then the OP does have a problem as it is not acceptable to
consider the conduit as a an earth as it will have mechanical joints
in it that may have suffered corrosion over the years The solution
is I'm afraid to pull the two cables back through, pulling in new
cables plus an earth cable.

I would suggest that the OP gets professional advise as his original
question does suggest that his knowledge of electrics is beyond such a
rewiring activity.

Rob