Fuses have different characteristics of operating time compared to current, characterized as, according to time required to respond to an overcurrent condition.
en.wikipedia.org Such short circuits are likely to result in a very high current and therefore quickly trigger an overcurrent protection device.
en.wikipedia.org Fuses only sense overcurrent, or to a degree, over-temperature, and can not usually be used independently with protective relaying to provide more advanced protective functions, for example, ground fault detection.
en.wikipedia.org These are robust, purpose-built amplifiers with many application-specific design features such as overcurrent protection and aggressive high-pass filtering for flyback voltage protection.
en.wikipedia.org Medium-voltage circuit breakers nearly always use separate current sensors and protective relays, instead of relying on built-in thermal or magnetic overcurrent sensors.
en.wikipedia.org