Home Inverters & UPS

List the essential appliances and total their wattage, then divide by 0.8 to get VA and add margin so the load stays under 80 percent of the rating. Typical homes with fans, lights and a TV need around 900 to 1100 VA, and homes with a refrigerator or pump need more. Start-up surge on motors needs extra margin.

A small window or split AC can be run by a large enough inverter and battery bank, but compressor start-up draws several times the running current, so the inverter must be sized for that surge. The battery also drains quickly because ACs use over a kilowatt. Most homes run an AC only on a high-capacity inverter or solar system.

A home UPS is built for computers and electronics, with a shorter transfer time and cleaner output, usually in smaller VA ratings. A home inverter is built for household loads such as fans, lights and a refrigerator, with a larger battery bank. Many products now sit in between, so check the transfer time.

Pure sine wave matches grid power and works with all loads, quietly and efficiently. Quasi or modified sine wave is cheaper but can cause buzzing in fans, heating in motors and trouble with sensitive electronics. Square wave is obsolete. For modern homes, pure sine wave is recommended.

A combo pack sells the inverter with a matching battery, and often a trolley, as one package, so the battery voltage, capacity and charging current are matched. It simplifies buying and installation. Check the battery type and Ah rating included, as it decides how long the backup lasts for your load.