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What is the difference between IEEE and IEC standards in terms of kW, kVAR, and PF (power factor)?

The following diagrams show the correlation between kW, kVAR, PF, and inductive or capacitive loads for both the IEEE and IEC standards.
NOTE: The lagging or leading distinction does NOT equate to an inductive or capacitive load. Rather, lagging corresponds to a negative PF, while leading corresponds to a positive PF (Lagging = -PF and Leading = +PF).

  • According to the IEEE convention, (right on the figure above), anytime the Power Factor is negative the load will be Inductive and anytime the Power Factor is positive the load will be Capacitive.
    However, according to the IEC convention, (left on the figure above), Power Factor sign is independent of the load being Inductive or Capacitive.
    Looking at Figure 1 it must be noted that, in either convention to determine a load Inductive or Capacitive all aspects of power must be taken into account, Watts, Vars, and Power Factor.


Legacy KB System (APS) Data: RESL204386 V2.0, Originally authored by MaTh on 01/25/2011, Last Edited by MaTh on 02/01/2011
Related ranges: Engineering Knowledge Applied to Power Management
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