An inverter is one of the most important things in your RV. It helps you convert your battery’s 12V DC into 120V AC, the standard house electricity output. This enables you can power all the appliances in your RV as you go down the road.
When choosing an inverter, you need to ensure to pick the right size that can reliably and safely power all the appliances in your RV.
However, picking the correct size of invert isn’t always an easy task for new and even seasoned RVers. If you’re one of these Rvers, the following quick guide will show you how to easily pick the right size of inverter for your RV.
What size of Inverter do you need for your RV?
First things first…
Before we discuss the size of the inverter you need, it’s important to understand what “Size” means in this context.
The size of an inverter isn’t about the physical dimensions. It’s about the number of wattages it a given inverter outputs. Knowing this size is crucial is it helps ensure you get the perfect inverter for powering RV refrigerator, TV sets, DVD player, cell phones, iPads/tablets, and all the other appliances you might have.
So, what size of inverter do you need?
The short answer: The ideal size of inverter for your RV depends on the appliances you have in your RV.
The Long answer: To get the right size of inverter for your RV, you’ll need to calculate the total sum of the wattage needed by the appliances and devices you’re using in your RV. The total value you get will give you the correct size of inverter.
BUT…it’s not wise to go for an inverter whose wattage output matches the total wattage of your appliances. We recommend you pick an inverter with higher wattage, say about 15-20%. This makes sense when you think that some electric appliances, especially the ones featuring an induction motor require up to 2x of their rated wattage when starting.
Calculating the wattage for various appliances on your RV is quite easy. You simply need to check the manufacturer labels on them (usually expressed in Amperes or simply amps).
Once you have gotten the sum of amps of your appliances, you’ll need to convert them into watts using the formula below:
Amps x 120 = Total Watts of your appliances.
The answer you will translate to the size of inverter you need.
But we mentioned that you should around 15-20% to the total watts. To do this, use the formula below:
Size of inverter = 15/100 x Total Watts of your appliances
Here is a real-life example of how to determine the perfect wattage for your RV inverter…
Let’s say you have the following items in your RV:
- TV set: 65 Watts
- DVD player: 35 Watts
- Light bulb (fluorescent): 25 Watts
- Microwave oven: 700 Watts
- Laptop: 120 Watts
- Stereo: 250 Watts
- Gaming console: 100 Watts
- Air conditioner for your RV: 700 Watts
- Cell phone: 50 Watts
To find the total wattage, add the wattages of the respective appliances:
Total Wattage = 65 + 35 + 25 + 700 + 120 + 250 + 100 + 700 + 50 = 2045 Watts
Add 15 to 20% extra overhead to the Total Wattage (in this case, we’ll go with 20%);
20/100 x 2045 Watts = 409 Watts
The Total Wattage = 2045 + 409 = 2454 Watts.
For this RV, you’ll need an inverter with a Wattage output of 2454 Watts. Needless to mention, you won’t get an inverter rated the exact value you get from your calculations.
In such a case, you should consider getting a model rated above your Total Wattage value.
In our example above, you’d want to go for a 3000 Watts inverter.
Quick TIP: Instead of going through the hassle of making all these calculations on a piece of paper, you might consider looking for an online calculator for RV inverter. These simply prompt you to enter all the appliances in your home and their corresponding wattages and then output the ideal size of the inverter to buy. Easy-peasy, right?
Other Things To Keep In Mind When Buying An Inverter
Now that you know how to determine the right size of inverter for your RV, what’s next? You’ll need to keep in mind a few things to ensure you get the best RV inverter.
These include:
Pure sine wave vs modified sine wave inverter
You’ll need to decide whether to get a pure or modified sine wave inverter. The big difference between these two inverters is the waveform output they produce.
A modified can run most (but NOT all) your appliances. It’s suitable running power tools, motors, non-digital microwave ovens, lights, pumps, and other appliances with DC brick power supply. Unfortunately, this waveform tends to interfere with some audio devices, TV sets, and TVs.
As for the pure sine wave inverter, it generates a cleaner output analogous. Most of these types of inverters can run just any device in your RV. However, keep in mind that pure sine inverters are higher priced than modified sine wave inverters.
Overload Protection
Overload protection is a helpful feature to have in your inverter. It automatically shuts down your inverter in case it experiences more power than what it’s engineered to hold. This will help prevent costly damages in your RV as well as ensure your safety.
Pro TIP: The RV inverters can easily drain your RV battery pretty fast, say when you have made a stop or you’re boondocking. To prevent thing, you should consider looking for a power inverter that automatically turns off when your RV battery voltage goes below 10V.
Bottom Line
After reading this guide, you should be able to understand what the size means in relation to an RV inverter. You should also be able to easily calculate the size of inverter you need to safely and reliably run all your RV appliances. And the additional factors to keep in mind when choosing the best inverter for your RV.
Have you calculated the size of your RV inverter already?
