Input Parameters
About This Calculator
- DC: I = P / V
- Single-phase AC: I = P / (V × PF)
- Three-phase AC: I = P / (√3 × V × PF)
- Breaker: Current × 1.25, rounded up
How this watts to amps converter works
Converting watts to amps uses I = P / V. For AC circuits, power factor must be considered.
Essential for circuit breaker sizing, cable selection, and distribution design.
FAQ
What is the watts to amps formula?
DC: I=P/V. Single-phase AC: I=P/(V×PF). Three-phase: I=P/(√3×V×PF).
How many amps is 3000W at 220V?
Resistive load (PF=1): 3000/220=13.6A. Recommend 16A or 20A breaker.
How to size a breaker from wattage?
Calculate current, multiply by 1.25 for continuous loads, round up to next standard size.