ceiling light wiring

[Kat74]

I've bought a new pendant light - the instructions say to wire live in the light fitting to live in the ceiling, neutral to neutral (using a jointing block).
But...all the wires coming out of the fitting are white (a whitish tranlucent casing round the cables). One of the 3 wires is slightly longer than the other 2 but other than that there is nothing on any of the 3 wires to differentiate them.
There is also an earth wire, but this attached inside celing rose part of the fitting - it' not connected, or even close to, the other wires. So assuming this is the earth, what are the 3 wires in the fitting?
I've changed 'normal' light fittings before but never come across 3 wires the same colour. Is there a way of telling which is live and which is neutral? If all else fails and I go for a trail and error approach, I assume the fuse and/or bulb would blow - is the worst that would happen ??
Thanks

 

[ban-all-sheds]

If it takes BC lamps then it doesn't matter.

If they are ES then use your multimeter to find which wire connects to the centre contact and which to the screw. The centre contact should be the live, the screw neutral.

Bit worried why you have a total of 4 cores to connect, though - can you post a photo?

As for the colours, are you sure it's not got normal cable with heat-resistant tubing over it?

Is the light CE marked?

 

[Kat74]

thanks for the reply B-A-S.
The light is CE marked and it's new, from a high street retailer so it should meet all regs.
The cables don't have any other colours under the casing - it looks like they just have the clear casing in place of the normal colours.

To try to decribe it better, there is a ceiling rose about, 20cm diameter, with a bracket inside for fixing to the ceiling. This rose is a hollow metal shape and on the inside of this there is a green wire attached, about 15 cm long. At the other end of this wire there is connection loop.
The cable that runs from the bit that holds the bulb (sorry - don't know the proper term!!) goes in, up through the centre of the rose. Out of this cable comes 3 separate wires. They are all the same colour and width but one is about 2 cm longer than the others.

I can't post a photo right now, sorry, but I'll have a go with the multimeter and if this doesn't give me any more clues I'll try to get one.
thanks!