What does "selective coordination" in an electrical system enable?

Selective coordination in an electrical system is essential for maintaining system reliability and ensuring safety during fault conditions. This concept enables downstream protective devices, such as circuit breakers or fuses, to operate during a fault without causing upstream devices to trip. Essentially, if a fault occurs, only the device closest to the fault will operate to interrupt the current flow, leaving the upstream devices undisturbed and allowing the rest of the system to function normally.

This capability significantly enhances the overall performance of the electrical system, minimizing downtime and reducing the potential impact on critical loads. By limiting the interruption to only the affected area, selective coordination helps ensure that larger segments of the system remain operational, which is particularly important in settings where continuous power is essential, such as hospitals or data centers.