Russell Baron
Hi Reginald, Is this a job you are wanting to do or something you've come across? If its something you want to do why would you want to use both? Generally we use 2.5mm on a ring circuit on a 32a mcb As long as the smallest cable size can carry the load being used on this circuit then its ok to mix but personally I wouldn't. Someone could see a 4mm cable and increase the mcb size and not realizing that further down the line is a length of 2.5mm which wont carry the load. Hope this helps a little Russ
