What is the primary benefit of proper protective device coordination?

• A. Faults clear with selective tripping to minimize disruption
• B. All devices trip at once
• C. Increases system impedance
• D. Reduced fault current

Answer: (A)

Selective coordination means arranging protective devices so that a fault is cleared by the device closest to the fault, with the proper speed, while upstream devices stay energized. This setup lets the nearest device trip quickly to isolate the problem, while the rest of the system continues to run. The result is minimum disruption to service because only the affected section is de-energized, and restoration is faster after the fault is cleared.

That’s why the best choice describes faults being cleared with selective tripping to minimize disruption. The other ideas aren’t the main benefit: tripping all devices at once would cause larger outages; changing impedance isn’t the goal of coordination; and reducing fault current isn’t what protection coordination primarily achieves—the fault current level is governed by the network, while coordination controls who trips and when.