Choose a 12V to 240V power inverter for caravan, 4WD, camping and off-grid use. StarPower stocks pure sine wave models from 1500W to 4000W, with options for remote control, multiple Australian outlets and USB charging. Compare the inverter’s continuous output, short-duration surge rating and connection requirements before ordering.
Choose the right power inverter
An inverter converts battery DC power into 240V AC power. Size it from the combined running wattage of the appliances you intend to operate, then allow for the higher start-up surge of motor-driven loads such as some fridges, pumps and power tools. A product’s peak or surge figure is not its continuous operating capacity.
| Nominal continuous output |
Approx. 12V input at full load* |
Typical selection consideration |
| 1500W |
About 139A |
Moderate caravan and camping loads, subject to appliance surge |
| 2500W |
About 231A |
Higher combined loads where the battery system can supply the current |
| 3000W |
About 278A |
High-power systems with suitable battery bank, BMS and cabling |
| 4000W |
About 370A |
Very high-current 12V installations requiring careful system design |
*Indicative current at 12V and 90% efficiency. Actual current varies with battery voltage, inverter efficiency and load. Do not use these figures as cable or fuse specifications.
Pure sine wave vs modified sine wave
Pure sine wave inverters provide a smooth AC waveform and are generally the preferred choice for sensitive electronics, chargers and motor-driven equipment. Compatibility still depends on the appliance manufacturer, its continuous demand and start-up surge. Check the appliance label or manual before selecting an inverter.
Battery, BMS, cable and fuse matching
A high-wattage 12V inverter can draw several hundred amps. Confirm that the lithium battery or AGM battery bank, battery-management system, interconnects, fuse and isolator can safely support the required current. Keep DC cable runs short, use correctly sized cable and over-current protection, and provide the ventilation clearances stated in the product manual. High-current installations should be designed and installed by a suitably qualified person.
Compare popular 12V pure sine wave inverters
For systems using 24V or 48V battery banks, solar charging and AC charging in one unit, compare our hybrid solar inverters. You can also explore MPPT solar charge controllers and DC-DC battery chargers when planning a complete off-grid system.
Power inverter FAQs
What size inverter do I need for a caravan?
Add the running wattage of appliances that may operate at the same time and identify the largest start-up surge. Select an inverter with enough continuous capacity and surge headroom, while also checking whether the battery, BMS, cabling and fuse can supply the DC current.
Does a 3000W label always mean 3000W continuous?
No. Some inverters use the peak figure prominently. Always check the technical specifications for both continuous output and short-duration surge or peak output.
Can a 4000W inverter run from one 12V battery?
Only if the complete battery system is rated for the very high current involved. At full output, a 4000W inverter may require more than 350A from a 12V system. Battery capacity alone is not enough: BMS limits, cable size, fusing, connections and voltage drop also matter.
How long will an inverter run from a battery?
Run time depends on usable battery energy, load, inverter efficiency and battery condition. As a rough energy check, divide usable battery watt-hours by the AC load, then allow for conversion losses. Real-world run time will be lower than the ideal calculation.
