I would like to thank you all or your replies, there has been a few new ones since i was last here. Would any of you know if there is a pat tester capable of testing 6mm cable, the one i use has a max size of 4mm which it says is 25 amp. I can do a manual test of earth bond with it, but i need to know the resistance of the cable at various lengths (110 volt 32amp extensions, arctic yellow). I have browsed bits of the IEE 16 Edition wiring regs and its way above me, i don't even know which section to look in and i think if i read the whole thing i am not going to get it.