What Is An RV Inverter?
In the most simple terms, an inverter transforms DC power into AC power. But why would you need to?
Alternating current (AC) cannot be stored, but direct current (DC) can, and we use our camper’s leisure batteries to store it.
You can wire your DC appliances to the battery, and they’ll run happily – things like LED lights, a 12v fridge, USB sockets, and ventilation fans.
Appliances usually plugged into a household power outlet need an AC power source.
Appliances like microwaves, laptop chargers, coffee makers, or regular TVs won’t run directly from the battery bank.
When a mains supply isn’t available, just like when you’re boondocking and the camper isn’t hooked up to shore power, you only have your battery bank as a power source, which provides DC power. But your household appliances won’t run on DC.
You could fire up your RV's generator because it produces AC power, but that can be noisy and a little overkill if you don’t need to use your household appliances often.
Instead, you can use an inverter to convert the battery bank’s stored DC power to AC so you can go ahead and run your household appliances.
Why Do I Need An Inverter In My RV?
The short answer is, you don’t. You don’t need an inverter if you can avoid running any AC appliances when off-grid. If your camper has a shore power electric hook-up facility, you can still run AC appliances when on a campground.
Battery banks have a finite amount of power. So whatever you use needs to be replaced, either from a solar setup, charging from the camper's alternator when the engine is running, or running a generator.
Limiting (or eliminating) the use of powerful AC appliances when not hooked up can help keep you off-grid for longer and may save the need for a large battery bank.
All that said, if you still want to run even a small number of AC appliances on batteries only, you need an RV inverter in your camper.
Some RVs already have an inverter installed. But if your camper isn’t one of them, the in-built inverter has failed, or you’re building a camper conversion, you can buy and install a separate inverter.
What AC appliances will you run at the same time?
The inverter needs to be powerful enough to run the AC components connected to it at any given time.
By minimizing what you have running simultaneously, you can reduce the size of the inverter you need.
For example, brewing your cup of joe before charging your laptop will need a smaller inverter than if you do both simultaneously.
What’s the highest power draw of your appliances?
Some appliances demand a power surge on startup. They take a significant power surge to get going before quickly dropping back to their running level. An induction hob is an excellent example of this kind of appliance.
It may run at an idle rate of around 300w per hour (so a 300w inverter would just about run it), but on startup, or when increasing the temperatures, it could pull as much as 1800w.
Inverters often have a peak rating greater than the continuous power rating, but we’ve not seen a small 300w inverter that can offer that kind of surge. In all likelihood, in this example, you’d need a 1000w inverter as it’s more likely to support the power surge needed.
You’ll need to check your appliance specifications for any surge demands.