Hi, as my profile says I'm not a sparky but I've wired up the odd light switch and socket! I know my limitations and take safety very seriously but I like learning. I have no intention of ever doing this but can someone explain who can remove the 100 amp fuse to a domestic CU. What is a "competent person" in layman's language? I've trawled the internet (dangerous I know) and can find no definitive answer.