— the operation of the fuses used in modern network filters is based on the heating of metals under the influence of electric current: the basis of such protection is a thin metal thread that melts when the current increases critically. Thus, in models where overload and/or short circuit protection is not provided, the fuse actually performs the function of such protection; if it is provided, the fuse plays the role of additional insurance in case of automatic failure. Such devices are extremely reliable, but after each operation they require replacement.
