> ...and a fuse doesn't blow at the stated current either - it normally > takes
> 150% for a second or something (there are British standards and things)
That's an anti-surge fuse; quick-blow fuses (the type more commonly fitted
in plugs) do indeed blow straightaway.
Over-current circuit breakers (as distinct from RCDs/ELCBs) act pretty
much as a quick-blow fuse.