##  [Power Factor](/power-factor) 

  ##  [Power Factor](https://engineering.quantumdictionary.io/power-factor-0) 

  

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**Engineering & Applied Technologies Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The ratio of real (active) power P delivered to a load to the apparent power S supplied in an AC electrical system, PF = P/S; in single‑frequency, sinusoidal steady state with linear elements PF equals the cosine of the voltage–current phase angle (cos φ).