Picture the scenario...
A double insulated Circular saw with twin core flex and a plug with a
13A fuse plugged into a house's ring main which has a 32A MCB at the CU.No other appliances are plugged in at the same ring main.
Hapless DIYer accidentally slices through circular saw's mains lead with spinning blade, creating a dead L - N short circuit.
RCD at CU does not pop due to no leakage current to earth as power tool's mains lead does not have an earth conductor.
Now the conundrum:
Which pops first, the 13A fuse in the circular saw's plug or the 32A MCB at the CU?
In case you need to know, the power rating of the circular saw is 1200 watts.
Discuss.......