Can anyone help confused homeowner... Put some new downlighters in my bathroom and hall way. So have a double light swich. But the old cabling has 4 cables. R,Y,BLUE,LIVE new cable has 3 B,BROWN,LIVE. Cant get the bathroom lights to work as i am only running 1 cable in the wall. How do I CORRECT IT!!! Am I allowed to as im the home owner. Thanks
I don't know the regulations, but I do know that if you don't know what cables you need you should call an electrician to come and do the job before you cause yourself or someone else some serious damage.
All fixed cabling in a house is protected by an earth wire (CPC) which will not carry a load except if it the circuit develops a fault. To do otherwise is suicidal at best and criminally negligent at worst.
The fact that you don't know what you're doing should really suggest that you should not be messing with electrics. Get a qualified electrician - don't mess with electrics period.
Bathroom electrics especially!