How to Choose the Right RV Power Invertert for Your RV
What RV Power Inverter Should I Buy?
It depends on what you're going to use it for. You don't buy a 20-ton truck to pull a 10-foot camper. You don't pull a large trailer with a tiny plastic car. If you only want to operate a computer or similar low-energy user, all you may need is a small (300 watt) inverter. If you're going to run a microwave or power tools, you may need a 1,200 watt or larger inverter. You may actually find it more efficient to have more than one inverter.
Types of RV Power Inverters
Not brand, but type. Just as there are types of engines (gas, diesel, etc.), there are types of inverters (or different technologies). Cost plays a part. You may still find low-tech, square-wave inverters for sale. They're grossly inefficient, using most of the electricity they consume just to run themselves. Their simple electronics lead to other problems also -- such as square TV pictures. If you're just going to run a simple item for a few minutes, you might get by with one of these but compare prices with power inverters using better technology... you may not much difference.
Technological advances have led to very sophisticated, solid-state inverters. From 100 to over 5,000 watts, ultra-efficient, with all sorts of advantages. Some of these use less than 10% of the energy consumed when fully loaded and way less than 1% at lesser outputs to operate.
At first glance, these Power Inverters are not cheap. But in terms of efficiency and the doller per watt cost compared to what you get out of them, they're cheaper than the less-efficient units.
Some can be held in your palm and simply plugged into a 12VDC receptacle. Other, larger output models, require elaborate installation. Some have features and options well worth an added cost.
What Size RV Power Inverter do I Need?
Do you want to use a Microwave or mutiple appliances at the same time? You'll need over 1,200 watts capacity. You'll also need at least 200AH (Amp Hours) of battery capacity (to run a microwave for brief periods). You'll need more battery reserve for longer periods and heavier loads. If you'll be cooking full dinners for 30 minutes, you'll need a 400AH battery capacity.
Just want to operate a TV or computer? Usually a 200 to 300 watt inverter is enough.
When it comes to buying an RV power inverter there are two ways to go:
One. Get a good, efficient 1,200W or larger inverter and feed the whole place. The best ones are 90+% efficient and no longer need to be matched to the load. They'll do nearly as well running a small load as a big one. Incredible but true.
Two. If you don't need a big inverter, consider having one or more smaller power inverters and use the size appropriate for the job at hand.
Maybe have an 800W for everything except a microwave. Perhaps a 300W for TVs, VCRs, stereos and satellite systems. A 200W palm-size may operate a small TV, small stereo, computer or breathing machine. The breathing machine is a prime inverter use. A palm size can be easily plugged into RV or tow vehicle cigarette lighter receptacle and can bring freedom to the camp-ground bound.
COST: The cost of power inverters, in general, has gone down over the years and they are more affordable now than they have ever been. But you need to compare barands and models carefully and be aware that the cheapest unit may not be the best 'deal'.
A good quality, brand-name 1,200+ watt power inverter may cost over $1,000. A power inverter made specifically for RV use may cost even more.
A "variety pack" may cost about the same as a singler large power inverter but probably less. And an advantage of having a variety... you don't have to buy all the power inverters at the same time.
RV BATTERIES: Technically, you can run anything you want from an inverter -- if it's big enough and you have enough batteries and if you have a way to keep the batteries charged. But an RV, while it may be a home, is not a homestead. Space and weight are considerations. So practically you woun't be able to run your aircoditioner on a power inverter. And you probably won't be able to run everything at once even with a large RV power inverter.
Small inverters can be used on a one-battery system with hardly any difference in amp draw. Large inverters will demand two batteries or four (or more) with heavy loads.
You may also want to read: RV Power Inverter Basics