An inverter, sometimes called a “power inverter,” is a piece of electronic gear that converts DC power to AC power, and it is what enables RVers to use regular household appliances in an RV without hookups to an RV park power pedestal relying on a generator.
The September/October 2016 issue of Escapees Magazine features our detailed article about inverters: what they are, how they are sized, what flavors they come in and how to wire one into an RV.
For RVers who enjoy dry camping in public campgrounds or boondocking on public land, an inverter is the key piece of the puzzle that gives their RV traditional 110 volt AC power — like the power in the wall outlets of a house — without plugging the RV into a power pedestal at an RV park or a noisy gas-hungry generator.
WHAT IS AN INVERTER?
- A converter converts the 110 volt AC power coming out of a wall outlet, RV park power pedestal or generator into 12 volt DC power, and charges the RV’s 12 volt battery bank.
- An inverter converts the batteries’ 12 volt DC power into 110 volt AC power so household appliances like the TV, blender, microwave and vacuum can run.
RV FACTORY INSTALLED CONVERTERS
Most trailers and some smaller motorhomes come with a factory installed converter. Frequently, these factory installed converters are inexpensive units that are not multi-stage chargers. So, for RVers who want to dry camp a lot and keep their batteries in tip-top shape, or charge them up efficiently with a generator while dry camping, it is a good idea to replace the factory installed converter with a better quality converter (we did).
More info on upgrading an RV power converter here: Converters and Inverters in an RV
RV FACTORY INSTALLED INVERTERS and INVERTER/CHARGERS
A few high end trailers and most higher end motorhomes come with a factory installed inverter.
In many cases, especially high end trailers, the inverter is dedicated to powering a residential refrigerator that runs exclusively off of 110 volt AC power (unlike an RV refrigerator that can run on propane). The inverter is there so the fridge can continue to run off the batteries while the rig is being driven from one RV park to another without a connection to 110 volt AC electricity. This inverter is sized to support the refrigerator and is not intended to be used for any other purpose in the rig.
So, for most trailer owners that want to do a lot of camping without hookups, an inverter is an extra piece of gear that must be installed.
In contrast, many higher end motorhomes come with a factory installed inverter/charger that can do two things: 1) provide the RV with household 110 volt AC power at the wall outlets via the batteries while dry camping and 2) charge the batteries when the RV is getting its 110 volt AC power from an RV park power pedestal or a generator. These inverter/chargers essentially do the work of both a converter (charging the batteries from shore power) and an inverter (providing AC power via the batteries while dry camping).
So, for folks with a higher end motorhome, an inverter is usually already installed in the motorhome at the factory in the form of an inverter/charger, and it does not need to be added later. However, it may not be a pure sine wave inverter (see below).
They are rated by the number of watts they can produce. Small ones that can charge a pair of two-way radios or a toothbrush are in the 150 watt range. Huge ones that can run a microwave and hair dryer are in the 3,000 watt range.
- Small inverters (400 watts or less) can be plugged into a cigarette lighter style DC outlet in the rig. Mark has one that he uses for his electric razor every morning.
- Larger inverters (500 watts are more) must be wired directly to the batteries and require stout wires that are as short in length as possible.
Our RV has a “house” inverter that is 2,000 watts. It can run our microwave and hair dryer and vacuum comfortably (we don’t run those appliances all at the same time, however, as that would overload it). Our small portable inverter lives in our bedroom and gets used for a few minutes every day before we head downstairs:
MODIFIED SINE WAVE vs. PURE SINE WAVE INVERTERS
Inverters also come in two flavors:
- Modified sine wave inverters mimic a 110 volt AC electrical signal’s wave form with a chunky square wave.
- Pure sine wave inverters (or “true” sine wave inverters) mimic a 110 volt AC electrical signal nearly perfectly.
Modified sine wave inverters are cheaper than pure sine wave inverters and are the most common type of inverter sold in auto parts stores, Walmart and truck stops. Many inverter/chargers on the market are modified sine wave inverters.
Our sailboat came with a 2,500 watt inverter/charger that produced a modifed sine wave. It was wired into the boat’s wall outlets, including the microwave outlet. We used this inverter when we wanted to run the microwave but not for anything else (we preferred using a pure sine wave inverter instead).
Some vehicles now ship with an inverter installed in the dashboard. Our truck has a small modified sine wave inverter in the dashboard, and I use it all the time to plug in our MiFi Jetpack and get an internet signal for my laptop as we drive.
WIRING AN INVERTER INTO AN RV – DC SIDE
As mentioned above, small inverters can plug into a DC outlet in the RV wall (these outlets look like the old cigarette lighters found in cars).
Large inverters must be wired directly to the batteries. The wire gauge must be very heavy duty battery cable and short to support the big DC currents that will flow through it. If possible, the length should be less than four feet. A wire gauge chart gives the correct gauge of wire to use for the current that will flow and the length the wire will be.
To determine the maximum possible DC current that might flow through these wires, simply divide the maximum wattage the inverter is rated for by the lowest voltage the inverter can operate at. In our case, we divided our inverter’s maximum 2,000 watts by the minimum 10.5 volts it will operate at before it shuts off. This yields 190 amps DC. Our cable connecting our inverter to the batteries is 2 feet long. So the proper wire size is 2/0 gauge (“double ought”) and can be purchased here: High quality Ancor Battery Cable.
WIRING AN INVERTER INTO AN RV – AC SIDE
All inverters have at least one household style female 110 volt AC outlet. Usually they have two. These outlets look like ordinary household wall outlets.
One very simple way to wire the AC side of the inverter is to plug an appliance directly into it, for instance, plug the power cord of the TV into the inverter. We did this with a 300 watt inverter and our 19″ TV in our first trailer. The inverter was plugged into a DC outlet on the trailer’s wall, and the TV was plugged into the inverter right behind where it sat on our countertop.
If you want to plug more than two appliances into the inverter at once, then plugging a power strip into one or both of the inverter’s AC outlets is one way to go. We did this on our sailboat. We had a 600 watt pure sine wave inverter on the boat. Plugged into one of the inverter’s AC outlets, we had a power strip supporting our TV and DVD player. Plugged into the other AC outlet, we had a power strip supporting everything else: two-way radios, toothbrush, and laptop charging cords and camera battery chargers.
Obviously, you have to be careful not to run too many things at once, or they will overload the inverter. Most inverters will shut down when overloaded or sound a beeping alarm if your appliances demand more from it than it can give. We ran into that a lot when we lived on our portable inverter for a few days while our house inverter was being repaired.
A more sophisticated way to wire an inverter’s AC side so it supplies power to all the wall outlets in the RV is to wire it into the rig’s AC wiring using a transfer switch.
WHICH INVERTER TO BUY for a BIG INSTALLATION?
Because we live off the grid and never plug our RV into a power pedestal (we’ve lived this way for nine years and hope to do so for many more), we rely on our trailer’s house inverter to run all of the AC appliances we own, every single day.
For this reason, we invested in the highest quality inverter we could find on the market: an Exeltech XP 2000 watt pure sine wave inverter. This is a very pricey unit, but it is our sole source of AC power day in and day out. It is the brand that was selected for both the American and Russian sides of the International Space Station, and its signal is pure enough to run extremely sensitive medical equipment.
Exeltech is a family run company with electrical engineering PhDs heading up their R&D department. All manufacturing is done in-house at their headquarters in Fort Worth, Texas. They have phenomenal tech support and an excellent warranty.
When our beautiful new Exeltech XP 2000 inverter was inadvertently blown up by a welding snafu at a trailer suspension shop during our trailer’s suspension overhual (the plastic sheathing on a bundle of AC wires got melted onto the trailer’s frame, bonding the wires to the frame and creating an electrical short — ouch), they got it repaired and back to us very quickly.
There are many other brands on the market from Schneider Electric / Xantrex to Go Power, Power Bright and others. If you are going to dry camp a lot, then installing a high quality and expensive pure sine wave inverter makes sense. But if you are going to dry camp for just a few days, week or month here and there, then a cheaper one may make more sense.
MORE INFO ABOUT INVERTERS and SOLAR POWER
All of this info and more is covered detail in our feature article in this month’s Escapees Magazine. We also have loads of other info about inverters, converters right here on our website. Links to our many RV electricity related articles are at the bottom of this page.
ESCAPEES MAGAZINE and RV CLUB
Our five page article on inverters in this month’s issue of Escapees Magazine is typical of the kind of detailed technical articles the magazine publishes.
I have been publishing articles like this in Escapees Magazine since 2008, and I have written about anything and everything we’ve learned in our full-time RVing lives, from solar power to photography to batteries to the importance of fulfillling our dreams.
What makes Escapees Magazine unique is that it is written by RVers for RVers.
The magazine article topics come from real life experiences that RVers have encountered in their lives on the road.
Just as my article in this issue of Escapees Magazine is about what we’ve learned about inverters since we started RVing (and believe me, back in 2007, I was the one asking trailer salesmen what the difference was between inverters and converters, and I got some wacky, wild and very wrong answers!), other RVers write articles for Escapees Magazine about things they have learned.
When I sat down to read the September/October issue, I was impressed — as I am with every issue — by the quality of both the articles and the presentation.
Besides including some cool travel articles about RVing Alaska via the Alaska Marina Highway ferry system, and visiting the Very Large Array that listens to the cosmos in New Mexico, and traveling on the Natchez Trace in Mississippi, this issue has two wonderful profiles of full-time RVers doing intriguing things as part of their RV lifestyle.
One article this month is about a full-time RVer who lives in an Airstream trailer and has dedicated himself to ensuring that the original silkscreen art prints created by the WPA artists in the 1930’s for the National Parks remain in the public domain, owned by the NPS rather than private collectors. It is a fascinating tale, written by Rene Agredano who has been full-timing since 2007 and writes the very informative blog Live, Work, Dream, a terrific resource for anyone who wants to learn the ins and outs of work camping.
Another article this month shares the stories of three very long term (10+ years) full-time RVers who have flourished as artists on the road. One RVer/artist specializes in watercolors and has held many exhibitions of her work around the country. Another RVer/artist discovered the fun craft of decorating gourds and teaches classes at her home RV park. A third RVer/artist has self-published a photojournal about her travels specifically for her grandchildren. This insipring Escapees Magazine article is written by full-time RVer Sandra Haven who shares the same home base RV park as the artists.
There is also a detailed article written by a lawyer on what it takes to establish a legal domicile and register to vote when you’re a full-time RVer without a sticks-and-bricks home built on a foundation that stays in one place.
These kinds of articles aren’t found in most RV industry publications!
And what’s neat for would-be writers and photographers who are Escapees RV Club members is that the magazine’s editorial staff is always eager for new material from members…click here!.
Escapees Magazine is just a tiny part of the overall Escapees RV Club, however.
Founded by full-time RVing pioneers Joe and Kay Peterson, the Escapees Club strives to serve the varied interests of all RVers and to alert RVers to changes in government policies or the RV industry itself that might affect us as consumers of RVs, RV and camping products and RV overnight accommodations.
They also work as tireless advocates on behalf of all RVers at both the local and national levels.
One of the most interesting articles in this month’s magazine alerts members to corporate consolidations in the industry that will affect our choices as RV consumers in years to come. It also reveals that the Escapees advocacy group is investigating possible changes at the Bureau of Land Management that will affect RVers ability to use their RVs on BLM land nationwide.
In addition to the magazine, the Club offers discounts for RV parks, regional chapter groups, national rallies, bootcamp training programs for new RVers, and assisted living for retired RVers who are ready to hang up their keys but not ready to give up living in their RV.
One of the most charming articles in this month’s magazine is about Nedra, a woman in her mid-80’s who was once an avid RVer but now lives at CARE, the Escapees assisted living facility in Livingston Texas. I had the good fortune to meet Nedra when we visited the Escapees headquarters at Rainbow’s End, and she took me on a fun tour of the CARE facilities. Escapees is like a big extended family, and it was very heartwarming to see her story in this month’s issue.
We’ve been members of Escapees RV Club since 2008 and highly recommend joining if you are a current or future RVer, whether you plan to travel full-time or just occasionally. Supporting their advocacy work benefits everyone who owns an RV and ensures we consumers and hobbyists have a voice in this very large industry.
You can join Escapees (or Xscapers, the branch of Escapees dedicated to younger, working age RVers) here:
If you mention this blog, Roads Less Traveled, when you join, they put a little something in our tip jar. We began recommending Escapees RV Club to our readers eight years ago, and this friendly gesture from Escapees is a brand new development in the last few months. So, this is not a sales pitch from us to earn tips, by any means. We simply believe in the work Escapees RV Club does to support RV consumers and hobbyists and hope you do too!
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SOLAR POWER OVERVIEW and TUTORIAL
- RV (and Marine) Solar Power Made Simple - An overview of how solar power works on an RV or boat
- Which Solar Panels To Buy? - What's Best: Flexible or Rigid Panels? 12 or 24 volt? Mono- or Polycrystalline? And WHY?
- Is RV Solar Power Affordable? - 3 solar power solutions for RVs and boats, including parts lists and actual costs
- Installing Solar Power on a Sailboat - How to overcome the unique challenges of solar power on a sailboat
- Solar Power Tutorial 1 - Basics - What makes up a solar power system and how does it work?
- Solar Power Tutorial 2 - Weekend/Vacation Systems - Everything needed for small "Weekending" and "Vacation" systems
- Solar Power Tutorial 3 - Full-time Systems - Describes the design of a "Full-time" system
- Solar Power Tutorial 4 - Solar Panel Selection & Wiring - Design considerations for choosing solar panels PLUS wiring tips
BATTERIES and BATTERY CHARGING SYSTEMS
- RV and Marine Battery Charging Basics - How do batteries get charged and what is the best charging method?
- Converters, Inverter/Chargers and Engine Alternators - No two battery charging systems do the job the same way.
- Solar Charge Controllers - How to optimize battery charging from the sun
- Solar Power and Shore Power Combined! - What happens when you're on solar and you plug into shore power?
- Wet Cell vs. AGM Batteries in an RV or Boat - Why we upgraded our RV house battery bank from flooded to AGM!
LIVING ON 12 VOLTS
- Inverter Selection & Installation - Choosing and installing the best inverter to support all our lifestyle's 120 volt AC needs
- RV Electrical System Upgrade - Which converter, inverter and batteries we upgraded to after 8 years off the grid, and WHY!
- How Much Inverter is Enough? - What happened when we accidentally killed our big inverter
- Clean Technica: Solar Power Installation on Sailboat Groovy - An analysis of our boat's solar power setup
- Kyocera Solar Showcases our Sailboat's Solar Power Setup - Sailing Groovy on Kyocera Solar Power!
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