If you’re new to RV and camper electric systems, terms like converter, inverter and charger can make your head spin. Many youtubers use these words interchangeably (or incorrectly) further adding to the confusion. Our goal with this post is to simplify and clear up these definitions.
DC Power vs AC Power
Before you can understand what an inverter or converter is, you should familiarize yourself on the difference between DC (direct current), and AC (alternating current) power. There are many distinctions – and we wrote an article about them – but for the sake of simplicity, here’s what you need to know:
AC power runs your typical household electronics. That means anything that plugs into a wall socket is using AC power. This is the power that runs in the electrical grid and power lines. You will most commonly see AC power in 120v or 240v form.
DC power is the type of power stored in batteries. Anything that plugs into a USB outlet or cigarette lighter uses DC power, and vehicles use DC power to run their electrical systems. Anything with a battery is using DC power internally. You can also power special made electronics like lights, water pumps and vent fans with DC power. You will most commonly see vehicle DC power in 12v form.
Here’s where things get tricky: When you park an RV at a campsite and plug into city power, you are using AC electricity (from the grid). When you travel off-grid and run a camper with a battery bank you are using DC electricity (from your batteries). Inverters and Converters allow you to switch between the two power sources
- Converters and Inverters are mirror functions of each other
- Converters turn AC power to DC power
- Inverters turn DC power to AC power
- You need a converter to get city power into your battery bank
- You need an inverter to run your household AC electronics from the battery bank
- An inverter/charger combines both a converter and an inverter
- The “charger” part of the name refers to a converter
|AC Power||DC Power|
|120v Household electronics||12v Battery bank|
|Hairdryer||12v Portable refrigerator|
|120v Household refrigerator||Cell phone|
As stated previously, you cannot charge a battery bank directly with 120v AC city power. You need to first convert that power into 12v DC form so it can be stored in the batteries; and that’s where converters come in.
Converters are often referred to as “chargers”, because their primary function is to charge batteries.
Your typical RV comes with a converter built-in. These are simple, single-stage systems which convert 120v AC power to 12v DC power and slowly charge up your battery bank while simultaneously powering your RV.
Converters work well when you’re plugged into city power frequently. This is the best solution when you spend all of your time at RV parks with hookups.
However, if you plan to travel off-grid often you should consider upgrading to a smart converter (multi-stage converter) because they are more efficient.
Smart converters (smart chargers)
Smart converters work just like converters, but charge batteries faster and more completely. A smart converter will sense how full your batteries are and adjust amperage and voltage to charge them in an efficient way.
They charge through four stages: bulk, absorption, float and equalize.
When the batteries are depleted, a smart charger ramps up the amperage until it gets near full capacity. Then it restricts amperages and increases voltage to top off and balance without throwing away extra power or damaging the batteries. This is known as multi-stage charging.
Why you should upgrade a converter to a smart converter
- Smart converters charge your battery bank faster, that is especially useful if you’re using a generator to charge your batteries.
- Smart converters are better for your long term battery health.
- Standard converters are not compatible with lithium batteries.
- If you’ve upgraded batteries from flooded to AGM or Gel, your old converter might be improperly charging them. This can damage the new batteries.
Upgrading your converter
Upgrading your converter is a relatively simple process. They are normally located underneath the AC breaker panel in an RV. We recommend these smart converters to upgrade to:
Installing an RV smart charger
If you want to go off grid and run a laptop, hairdryer, coffee pot, microwave or anything that plugs into a standard household wall socket, you’re going to need an inverter.
Inverters are the opposite of converters. They take 12v battery power and turn it into 120v AC power.
Inverters are popular in van life, but they are only as good as your battery bank. You’ll need replace the power you use with either an inverter charger, generator, or with solar panels and a charge controller.
Inverters combined with smart converters are called inverter chargers. They can charge your battery bank with city power and also provide power to run household electronics from your batteries. This is the best of both worlds.
Why you should upgrade a converter to an inverter charger
- They can charge your battery bank.
- They have all of the benefits of a smart converter.
- You can use all of your electronics off-grid.
- One unit does the job of two devices.
- Most come with an automatic transfer switch so you don’t have to manually turn them on and off like a standard inverter.
- Many inverter chargers have an automatic generator start feature. If the batteries drop too low, the inverter will send a signal to the generator to turn on and run until they are topped off again. This will keep the battery bank full and the electricity flowing without a touch.
- They are compatible with all battery types.
Is an inverter necessary?
You can rely on battery power and 12v electronics when camping off-grid. Many van lifers choose to go this route because it is simple. If you don’t have an inverter you can still use lights, vent fans, 12v portable refrigerators or other small electronics. You just won’t have any powered household wall sockets.
Inverter chargers are significantly more expensive than a smart converter. If you don’t plan to do a lot of boondocking, save yourself some money and stick with a smart converter.
The Best Inverter Chargers For RV
Installing an RV Inverter Charger
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