Yes, using an inverter with a higher wattage rating than required is typically safe and can be advantageous. . Consequently, inverter sizes vary greatly. During our research, we discovered that most inverters range in size from 300 watts up to over 3000 watts. In this article, we guide you through the different inverter sizes. Additionally, you'll learn what appliances you can power and how you can select. . An inverter's size, typically measured in watts (W) or kilowatts (kW), should match the power demands of the devices you intend to run. Start by listing the devices you want to power and noting their wattage. Use the total wattage, plus 20%, as your minimum power requirement. Note: The wattage's given below are estimates. The actual wattage required for your. . Minimum Inverter Size: The smallest inverter that can handle your highest-wattage appliance. Maximum Inverter Size: The inverter size required to run all your listed. . If I am correct, the max Wattage I can push in would be 240V x 50 amps = 12kW. This means I should buy a generator that can feed 12kW (or perhaps slightly more to be comfortable) as buying a 20kW generator would be a waste of 8kW power. Am I correct in this assumption? Thank you! Depends. Introduction: Why Inverter Size Matters An inverter converts DC power (from batteries or solar panels) into AC power (for household appliances).