I've got a 12V power adaptor (3.8A). And it got two fuses in it (T3.15AL250V, 3AL250V, one of which (3.15A) has blown, along with mosfet, current sense resistor, 450V cap, and IC. I replaced all failed parts, except the fuse (soldered jumper, since I don't have 3.15A fuse for now).
What is the point of two fuses in series? I've never seen anything like this before.