Which term describes the electrical power that is actually available to drive the pump after losses in the drive system?

• A. Available Power
• B. Input Power
• C. Apparent Power
• D. Reactive Power

Answer: (A)

The power that actually drives the pump after accounting for drive-system losses is the useful, real power available to do work. This Available Power is what remains after motor, controller, and mechanical losses are considered, and it equals the input power multiplied by the overall efficiency of the drive.

Input Power is simply what’s drawn from the electrical source before losses, so it’s higher than what actually powers the pump. Apparent Power combines voltage and current without regard to how much of that power is actually doing work, since it ignores the phase difference. Reactive Power represents energy that shuttles back and forth between the source and reactive elements and does not perform net useful work. Thus, the best term for the power truly available to drive the pump is Available Power.