Question 1

How do I calculate inverter VA?

Accepted Answer

Divide the total connected watt load by the inverter power factor. This calculator assumes 0.8 and adds reserve margin.

Question 2

How do I calculate battery Ah for backup?

Accepted Answer

Multiply load watts by backup hours, then divide by battery voltage and efficiency.

Question 3

Why add reserve margin?

Accepted Answer

Reserve margin helps handle starting surges, inverter losses, battery aging, and real-world load variation.

Question 4

Can I run an AC on this inverter estimate?

Accepted Answer

This calculator is intended for common home loads like fans, lights, and TV. ACs need separate surge and compressor-load sizing.