Odd having three sets of wires for one light?
If your new light fitting really does have three sets of wires then connect all the brown wires to Switched Live in the ceiling rose and all the blue wires to the neutral connector of the ceiling rose. The green and Yellow wire is the earth - connect it to the earth terminal of the ceiling rose.
When fitting a new light to an existing ceiling rose none of its wires connects to the Live terminal - only to the Switched Live terminal - so you can turn the light on and off - and neutral for the return path.
A common mistake is to confuse the Switched Live wire (from the Switch) with a Neutral wire - it isn't, it's live when the switch is on but often has the same colour as a neutral wire so as a safety measure it should be sleeved either Brown or Red to show that it's special.
Go here... to see a ceiling rose with the new European wiring colours and a light attached.
http://www.flameport.com/electric/lighting_circuits/lighting_ceiling_rose_looped.cs4
Take care...
Peccavi
June 2009
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