Inverter Sizing Calculator

Calculate the inverter size needed for your AC loads, accounting for surge requirements and efficiency.

W
x
%
V

Minimum Inverter Rating

1,000 W

DC Input Current (continuous)46.3 A
DC Power Draw556 W

Minimum Inverter Rating vs Continuous Load

Inverter Sizing

Formulas

Inverter Rating = Continuous Load x Surge Multiplier

DC Current = AC Load / (DC Voltage x Efficiency)

Motors and compressors draw 2-3x surge at startup. Size the inverter for the surge, not just continuous load.

Example Calculation

500 W continuous load, 2x surge, 90% efficient inverter on 12 V DC.

  1. 01Minimum inverter = 500 x 2 = 1000 W
  2. 02DC current = 500 / (12 x 0.9) = 46.3 A
  3. 03DC power = 500 / 0.9 = 556 W

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