When you reach into your fridge for that cold drink, do you wonder how it stays cold when the RV is not plugged into power? Today, we are walking through the basics of RV electrical. We will show you step by step or should I say component by component how that coffee pot turns on when you boondock. So let’s talk about what you need to know about RV electrical.
RV Electrical Diagram
Above is a diagram of an average RV electrical system. Not every RV electrical system will look exactly like this one. But they will be similar. The diagram has been simplified in an effort to make it easier to follow. But even simplified it can be confusing. So let’s back up and take it step by step and component by component!
Before we dive in this is where I tell you neither of us are electricians, or RV experts or RV technicians. We are RVers just like you and we are sharing what we have learned along the way. And trust me when I say if I can learn this stuff anyone can!
You just found an epic boondocking location, and you want to stay there as long as possible. Can you power the fridge? Will you be able to brew a pot of coffee? Of course, you can! This is where we’ll start. That’s right, our review of power will begin without power!
If you have solar panels this is the place power will enter your RV while boondocking. We are of course assuming it is a beautiful, sunny day and you are not parked under shade trees. (We will address rain and clouds a little farther down in the discussion).
Warm, beautiful sunshine is absorbed by the solar panels. The solar panels will turn the sun into energy and send it to your solar controller.
The solar controller regulates the power produced by the solar panels. It prevents too much power from going to the batteries all at once and prevents the batteries from overcharging.
The power will travel from the solar controller to the batteries. Speaking of batteries, do you know what type of batteries are in your RV? Have you seen them lately? Do your batteries require maintenance? We will go over the types of RV batteries and which is the best fit for your camping style in our next blog post. So be sure to come back and check that out!
****If you don’t have solar power you can skip over the solar power section and enter the diagram at the batteries.
Let’s continue down the power trail. As the current leaves the batteries it will come to a fork in the road. Your batteries will send power in two different directions.
RV batteries are 12 volts (V) direct current (DC) current so any items that use 12 volts DC power can easily accept power from the batteries. The batteries send power to the DC fuse box and the fuse box sends the power to items such as water pumps, USB ports, smoke detectors, fantastic fans, and some lights.
The second location the RV batteries send power is to the inverter. The inverter may be a stand-alone unit in your RV or it may be a combo unit. Combo units are able to invert, convert and charge (more on that in a bit). Not all RVs will have an inverter. Does yours?
The inverter is very important. It takes 12V DC power and inverts it to 110V Alternating current (AC). Electrical outlets run on 110V AC power so this allows you to run your appliances on your batteries while unplugged.
After power leaves the inverter in its new 110V form, it heads to the AC breaker box. Power leaves the breaker box and goes to your outlets powering all of your favorite appliances including the refrigerator, hairdryer, instant pot, water heater, coffee maker (most importantly) and any other item you plug into your regular outlets.
AC vs DC
Let’s take a minute to talk about AC and DC current for those who need a little clarification.
The power that flows in a sticks and bricks is called alternating current (AC). The direction of the current reverses, or alternates, 60 times per second. This is the power you use every time you plug an appliance into an outlet.
Batteries and solar cells produce direct current (DC). The positive and negative terminals of a battery are positive and negative and current flows in the same direction between those two terminals.
Boondocking on Cloudy Days
In a perfect world, every day is sunny and the skies are always blue. But if you are caravaning with us you know that is not always the case. Occasionally, we feel a little like Linus with a black cloud hanging around. How do we charge the batteries on days when there is no sunshine? For us it’s easy! We go old school with our generator.
If you don’t have solar the generator will be your lifeline when you are unplugged. During our first year as full-time RVers, we used our generator exclusively for power while boondocking. We discovered so many magical locations that first year. Thank goodness we were not afraid to turn on that generator and give boondocking a try.
There are many different brands, sizes, shapes and colors of generators that can be used while RVing. We have an onboard generator that is standard with our RV. If your RV does not come with an onboard generator you can purchase one for boondocking.
But please, do your homework. Not all generators are the same. After you choose the generator size that is best for your RV take a look at the decibel levels. Please, purchase the quietest generator that you can afford. Trust me after listening to the generator for 6-8 hours a day for a week you will wish you had spent the extra cash for fewer decibels! And for the love of Pete, PLEASE love the birds and your neighbors enough to leave your coal eating, construction grade, deafening generator at home!
If you are looking for a generator the Best Quiet RV Generators – Decibel & Noise Test is a great place to start!
RV Electrical with a Generator
When you turn on the onboard generator it sends power to the transfer switch. The transfer switch attaches the generator to your electrical system. It switches the electrical input between the generator and the power pedestal. The transfer switch prevents electrical input from entering the RV from both sources at the same time.
The power produced by the onboard generator is 110v which enables it to travel from the transfer switch to the AC breaker box. The AC breaker box sends power to two locations. The first location is the 110v outlets to power all the appliances as we discussed earlier in the boondocking section.
***If you do not have an onboard generator you will not have a transfer switch.
The second component to receive power from the breaker box is the converter. The converter will change the power from 110vac to 12vdc. Every RV will have a converter installed. Without it, you will not be able to charge your batteries.
Your RV may have a device as we mentioned above that that is capable of tackling several jobs. The device we use is a Magnum 3000 watt 12v DC hybrid inverter/charger. This monster of a machine will convert 110 volt AC power to 12 volt DC power. It will invert 12-volt power to 110 volts. And it also assists in the charging of our batteries.
Back to the subject at hand: The power flow through your RV.
The inverter sends power in two directions. First, to the DC fuse box which sends power to all the 12v items in your RV as discussed above. Second, power is sent to the batteries. This is how your batteries are charged by the generator while you are unplugged from shore power.
I bet you are ready to find those epic views and unplug for a bit! I know I am!
RV Electrical Power
Now that you know the route of power while unplugged, the rest is easy! When you plug your 30 or 50 Amp cord into the power pedestal (after you turn off the breaker of course! Don’t get me started on that one!) the direction of the current is very similar to the generator.
The power travels down the power cord into the transfer box. The transfer box sends the power to the AC breaker box. After that, the power travels the same route as the generator. And that’s it! See easy right?
As stated earlier if you don’t have an onboard generator then you won’t have a transfer switch. Power will flow from your 30 or 50 amp cord straight to your AC breaker box.
Your RV Electrical
It is important to understand that your RV may have different components than ours. Knowing what components your RV has installed will allow you to understand the power capabilities of your RV. While every RV has a converter, not every RV has an inverter. The goal of this article was to help you understand each component and what it can do for you. Now get out there and open some doors!
RV Electrical Diagram without Solar
The diagram below is the completed diagram without solar power.
RV Power Assessment
If you need help assessing your power usage there are some companies that will help you. Battle Born Batteries is one of those. If you are planning to upgrade to Battle Born lithium they will help you figure out your electrical needs. The decision of how much solar or lithium you need in your RV will depend on the number of amp hours you use on a daily basis.
RV Electrical: What You Need to Know Walk Through
More RV Electrical Information
We just tipped the basics of RV Electrical. If you want to dive in a little deeper we have just the place for you. Matt from Adventurous Way did a presentation at the Escapees Bash this year discussing RV power. That presentation is now on his YouTube channel. He is a smartie and does an excellent job teaching!