Connecting power to a LED illuminated mirror and a LED batten in Loft

[psarinuk]

Hi all,
The previous owner left me a wire hanging in the bathroom which has now been connected to a newly installed LED mirror.
The other end of that cable is in the loft, it is taped to 3 other 1.5mm T/E cables that feed into a spot light in the same bathroom below.

Questions:
1. Should one of these 3 cables in black electrical tape be 240V LIVE?
2. If the answer to above question is YES, can I just connect the currently dangling cable in loft with the LIVE cable to allow power to LED mirror?
3. Lastly, I am told that we need some light in the loft, so can the same LIVE cable be used to feed a switch to allow using a LED batten?

Many thanks for your advice in advance.

 

[ericmark]

Putting it simple, one can't assume. It may well have all the connections you need, but it could also be lacking some, lights will work with just a line and neutral (both classed as lives) but often not safe without an earth.

My main DIY tester will do most of what I need, I also use a insulation tester but I don't have an earth loop impedance tester or a RCD tester when I want them I have to get them back off my son, but the whole problem with DIY is we try to get away with out buying expensive testers. The two shown cost me £70 the testers my son has annexed would likely add another £500 to replace.

So step one what have you got? I find the non contact voltage test being shown in use with the first meter is a very good start point, note start point, pictures do help, but without some testing can't really answer your question.