
Your RV Has Two Power Systems
RV electrical systems aren’t as complex as you might think. Did you know your RV has two power systems? Most RVs have one or more batteries that power things like the lights, tongue jack, water pump, vent fans, and more. These batteries are referred to as “house batteries.” This system works even when you are not plugged into shore power so you can camp without plugging in.
12-Volt DC RV Electrical System – House Batteries
Your house batteries may require maintenance depending on the type you have. The most common type is a flooded lead-acid battery. This type of battery will need to be checked regularly to make sure there is enough distilled water in each cell. It’s important to know where your batteries are and what type.
Sealed batteries don’t require any maintenance. My RV has two house batteries. I replaced them about a year ago because the old ones were failing. I have AGM (Absorbent Glass Mat) batteries. I choose them because they last longer, hold a charge better, and require no maintenance. They are slightly more expensive than lead-acid batteries.

My new batteries took a beating from my inadequate charge controller. They were overcharged repeatedly to the point they weren’t able to hold a charge. This made things very difficult when I needed my batteries. There is a detailed post about my charge controller replacement here. Your RV Charge Controller Damaging Your Batteries?
Another popular choice for RVers is lithium batteries. These are significantly more expensive at around $800 to $1,000 each. RVers who have invested in a solar setup tend to prefer these batteries. I’ve seen as many as 6 used in one RV. This allows you to store a great deal of power. If you have an onboard inverter, you can even use your regular wall outlets.
Shore Power – 120 Volt AC System
The second system is your 110-volt electric system. This is powered by plugging your power cord into a power source such as the power post at an RV park or a generator.
Your RV will have a 30 or 50-amp power cord to connect your RV to shore power. Some power cords are permanently wired into the RV and some detach from both ends. To use your 110-volt electrical system just plug your RV power cord into an electrical source such as the power pedestal at your campsite (and into the RV if necessary). Always make sure the breaker at the power source is off before you plug your power cord in then flip the breaker to the on position. Turn the breaker off before you unplug your power cord.
Breaker and Fuse Box
Your RV will have a breaker box and a fuse box somewhere inside. It’s a good idea to know where they are located and keep extra fuses with you.
Invest In A Good Quality Surge Suppressor
One of the best investments you can make to protect your RV from power surges is a surge suppressor. One hit from a power surge and you can fry your entire RV electrical system. It’s a chance I’m not willing to take. I have a Progressive Industries which has a lifetime warranty. I actually had mine replaced once and it went very well.
Progressive Industries 30 amp surge suppressor.
Progressive Industries 50 amp surge suppressor.
There is a lot more to know about RV electric system but this is a good, basic beginning. KOA has a detailed page about RV electrical systems.
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Is Your RV Charge Controller Damaging Your Batteries?
Is Your RV Charge Controller Damaging Your Batteries?
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