Inverters Explained: Pure Sine, Modified Sine & Inverter/Chargers (2026)

Inverters are the component that turns your battery’s DC power into the household AC that runs normal appliances — and the category confuses buyers because three quite different products share the name. This guide explains what an inverter does, the difference between a plain inverter and an inverter/charger, and how to choose the right type for your rig.

What an inverter does

Your battery stores DC power; most appliances need 120V AC. The inverter bridges that gap, converting DC into AC so a normal wall-plug device works from your battery bank. Native 12V loads — lights, the water pump, USB charging — skip the inverter, but anything with a standard plug goes through it.

Type 1: Pure sine vs modified sine

The first fork is the waveform. A pure sine inverter produces clean, grid-quality power that runs everything safely. A modified sine inverter is cheaper but produces a coarse waveform that can buzz, overheat motors and damage sensitive electronics. For any rig you live in, pure sine is the answer — the full comparison is in pure sine vs modified sine.

Type 2: Plain inverter vs inverter/charger

The second fork is whether it also charges. A plain inverter only converts DC to AC. An inverter/charger combines three functions in one box: it inverts, it charges the battery from shore power or a generator, and it transfers automatically between sources — so when you plug into shore power, it stops inverting and starts charging without you touching anything.

For a simple setup that only runs a few devices off-battery, a plain inverter is cheaper and sufficient. For a full-time rig that moves between boondocking and hookups, an inverter/charger is the cleaner, integrated solution — and it is why units like the Victron MultiPlus and Renogy inverter/chargers exist.

Type	Does	Best for
Plain inverter	DC → AC only	Simple off-battery use
Inverter/charger	Invert + charge + transfer	Full-time rigs, shore + solar
Pure vs modified sine	Clean vs coarse power	Always choose pure sine

Sizing and choosing

Whichever type you choose, size it to your largest simultaneous load plus surge, and — the step people skip — confirm your battery’s BMS can supply the current the inverter draws. A 2,000W inverter pulls about 175A at 12V, which many 100Ah batteries cannot deliver. The full method is in how to size an inverter, wiring in inverter cable sizing, and installation in the inverter installation guide. Electrical standards are at the National Fire Protection Association.

Frequently asked questions

Do I need an inverter or an inverter/charger?

If you only run devices off the battery and charge it separately, a plain inverter is cheaper and enough. If you move between shore power, generator and battery and want automatic switching plus battery charging in one unit, an inverter/charger is the integrated choice for a full-time rig.

Pure sine or modified sine?

Pure sine for almost everything — it runs sensitive electronics, motors and medical devices safely. Modified sine is cheaper but can damage or degrade these. For a rig you live in, the small saving is not worth the risk.

What size inverter do I need?

Size it to the largest total load you will run at once, plus surge headroom for motor startups, then confirm your battery’s discharge limit can supply the current. Most RVs land on 2,000W; induction cooking or heavy tools push toward 3,000W.

Can my battery run the inverter I want?

Only if its BMS supplies the current the inverter draws. A 2,000W inverter needs about 175A at 12V, and many 100Ah batteries cap at 100A. Check the battery’s continuous discharge rating, or move to a larger battery, two in parallel, or 24V.

Last updated: July 24, 2026. Figures are typical; verify against your specific appliances and battery specifications.