If a system is not selectively coordinated, what is a likely consequence?

If a system is not selectively coordinated, what is a likely consequence?

• A. Increased Reliability
• B. Unnecessary Power Loss to Loads That Should Be Unaffected
• C. No Effect on the system
• D. Higher Voltage Drop

Answer: (B)

Protection coordination means the protective devices are arranged so that only the device closest to a fault interrupts. When coordination is not selective, a fault can trigger upstream devices as well, pulling the power down for portions of the system that aren’t actually affected by the fault. The result is outages that remove power from loads that should remain energized, which is the most likely and direct consequence. While broader outages could also be discussed, the key issue here is the unnecessary loss of power to unaffected loads. Voltage drop changes are not the primary outcome of losing selectivity.

Protection coordination means the protective devices are arranged so that only the device closest to a fault interrupts. When coordination is not selective, a fault can trigger upstream devices as well, pulling the power down for portions of the system that aren’t actually affected by the fault. The result is outages that remove power from loads that should remain energized, which is the most likely and direct consequence. While broader outages could also be discussed, the key issue here is the unnecessary loss of power to unaffected loads. Voltage drop changes are not the primary outcome of losing selectivity.