Cable downsizing - lighting circuit

[DNS1]

Hi guys,Got a kitchen on the end of a downstairs radial. 6A MCB, all in 1.5mm.Adding 3 further points on the end of the circuit (main ceiling light + undercupboard lights). Can I downsize the cable to 1mm?Current capacity is still fine (method c).Excuse the stupid question, but I can't find the relevant reg.

 

[malcolmsanford]

Which relevant reg are you looking for, there isn't one concerning that you can't reduce the size of a cable CSA in the same circuit, but quite a few that advise you can throughout the regs, under certain conditions.

 

[a1guvner]

im sure you have to class the whole circuit as the smaller dia, for calcs and certs, might be wrong

 

[tony mc]

My view would be as long as the Iz => In=> Ib is ok then it would be ok.


Would it not be better to keep it with 1.5mm for the sake of a few meters of cable ?