Customer: I have a 24 v to 5 v, the power of 2 w dc power supply module, the input side has a 1 a self recovery fuse, now have such a case, the output of the when I short circuit, voltage (mv) at this time may not be electric, but long time short circuit, since recovering the smoke, power supply module, burn out insurance didn't play a role, excuse me, how to guarantee the short circuit, components will not be burned?

Large capacity electronics engineer reply: should choose the self-restoring fuse of about 0.1A.

Option 1 a fuse generally thought current in more than 1 a began to work, when work after the current basic there are about 4 a, under current so far exceed the power module, power supply module burn out.

Self-recovery insurance smoke, this phenomenon is not easy to explain, may be overpressure or the back end of the burning.