Lighting
Power Factor (PF)
01 — Definition
The ratio between real power (watts) and apparent power (volt-amperes) on an AC circuit. PF 1.0 is the ideal; PF 0.5 means half the current drawn goes into reactive. LED drivers typically run between PF 0.7 and 0.98. To size a circuit you work in VA (volt-amperes = watts / PF), not in watts alone.
02 — In the field
A 600 W LED wash at PF 0.85 draws 706 VA, not 600. On a 230 V circuit that is 3.1 A instead of 2.6. Add 15 to 20% to your circuit loading to absorb power factor on LED-heavy rigs.