What Is Power Factor
Power factor describes how effectively electrical power is converted into useful work. Understanding it helps explain why some loads draw more current than their wattage alone would suggest.
What power factor measures
Power factor is the ratio of real power (kW), which does useful work, to apparent power (kVA), which is what the supply actually delivers. A power factor of 1.0 means all delivered power is used productively.
Why it matters
A low power factor means a circuit draws more current than necessary for the real power it uses. That extra current increases conductor heating and reduces system capacity, even though it does no useful work.
What causes it
Inductive loads such as motors and transformers cause current to lag voltage, producing reactive power. The larger the reactive component relative to real power, the lower the power factor.