A current limiting protective device will cut off the maximum peak fault current for currents within its current limiting range that is less than what duration?

A current limiting protective device is designed to reduce the maximum peak fault current that can flow in a system during a short circuit or fault condition. The ability to limit the fault current effectively is crucial to protecting equipment and minimizing damage during such events.

The correct answer indicates that the device will cut off the maximum peak fault current for currents within its limiting range that are less than 0.5 cycles in duration. This duration is significant because it reflects the rapid response time of the device. By limiting the fault current to this timeframe, the device can prevent excessive heat and mechanical stress in electrical components, which occurs due to high fault currents.

In practical terms, when a fault occurs, the time it takes for a device to interrupt the fault current directly correlates to the peak level that could be experienced in the system. Since many electrical components have a thermal and mechanical withstand capability that is time-dependent, a quicker interruption leads to significantly less damage.

The other durations offered (1 cycle, 2 cycles, and 3 cycles) would imply that higher fault currents could persist longer, potentially causing more severe damage to the electrical system and its components. Therefore, the emphasis on cutting off fault currents under 0.5 cycles highlights the protective device's design efficiency in