Calculadora de fator de potência
Calcule o fator de potência a partir de watts e VA: FP = W ÷ VA. Útil para nobreaks e cargas em CA.
Watts doing useful work.
VA from UPS, inverter, or AC equipment ratings.
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Table of Contents
What power factor means
Power factor (PF) tells you how effectively AC current is converted into useful real power.
PF = W ÷ VA. A PF of 1 means real and apparent power are equal.
Lower PF means higher current for the same useful watts, which impacts capacity planning.
This calculator complements our VA to Watts and Watts to VA tools.
Formula
Power factor from watts and VA
PF = W ÷ VA
For common AC loads, PF is between 0 and 1.
Related forms
W = VA × PF | VA = W ÷ PF
If PF = 1 (resistive assumption), watts and VA are equal.
How this links to other electrical formulas
Real AC power uses W = V × I × PF (single-phase) and W = √3 × VL-L × I × PF (balanced three-phase, line-to-line).
Quick Reference Table
| Watts | VA | PF | Typical load |
|---|---|---|---|
| 900 W | 1000 VA | 0.90 | UPS rated 1000VA/900W |
| 600 W | 1000 VA | 0.60 | Motor-heavy or legacy load |
| 1200 W | 1500 VA | 0.80 | Mixed office equipment |
| 1980 W | 2200 VA | 0.90 | Modern active-PFC systems |
FAQ
For standard AC real/apparent power definitions, no. PF is typically between 0 and 1.
It depends on context, but higher PF generally means more efficient use of current for the same watts.
Lower PF means more apparent power/current is needed to deliver the same real power.
They are inverses: with watts and VA you get PF; with watts and PF you get VA.