A poorly or improperly maintained OCPD can result in higher actual incident energy during an arc flash incident than determined by an incident energy analysis.

• A. True
• B. False
• C. Not Applicable
• D. Sometimes

Answer: (A)

The main idea is that arc flash energy depends on how much current flows and how long it continues to flow before the fault is cleared. The incident energy analysis estimates energy based on the protective device operating as intended. When an overcurrent protective device is poorly or improperly maintained, its actual performance can deviate from those assumed characteristics—trip times may be slower, the device may not trip reliably, or upstream devices may not coordinate correctly. That means the fault can persist longer than the analysis predicts, or the arc can stay energized longer, resulting in a higher actual I-squared-t energy than was calculated. So, a poorly maintained OCPD can lead to higher actual incident energy.