fuses and automatic switches

What is an automatic fuse and switch? Fuses, switch-fuses, and automatic switches are used to protect lighting installations, industrial electricity, wires and cables, and machines against overload and short circuit current. However, fuses can not always perform local and selective protection in different types of networks completely (means without error). Also in the three-phase network, when current increases, it is often necessary to cut three phases simultaneously. Therefore, fuses and switch-fuses can not always be used.