Fundamentals of Load Calculations for Electrical Engineers

A: This approach achieves a connected load that respects NEC continuous load treatment without double-counting diversity. Option A fails because breaker sizes are protective limits, not operating currents. Option C confuses physical capacity with expected demand. Option D imports a rule-of-thumb that belongs to derating, not load calculation.

A: This choice preserves the mechanical output by accounting for higher electrical input at lower efficiency. Option B assumes a VFD with kW control that isn't stated. Option C mixes up power factor effects with bus regulation. Option D ignores that losses still draw from the supply.

A: This path achieves contractual compliance and avoids unapproved scope creep. Option A sounds safe but breaks contract control and MOC. Option C creates a non-code condition that's hard to defend in DFMEA. Option D confuses installation jurisdiction with design obligation.

A: This answer highlights a failure mode that load calcs must catch before protection ever acts. Option A is exactly what overload protection is meant to address. Option B sits in the instantaneous trip domain of the device. Option D can be mitigated indirectly by sizing but isn't the primary blind spot.