RV Electrical System: A Tale of Two Voltages
Your RV electrical system is pretty simple. With a little help you should have no problem figuring it out and being able to troubleshoot it when the time comes.
An RV electrical system consists of two different systems with two different voltages. A 110-120 volt AC system and a 12 volt DC system.
When talking about the AC side of your RV electrical system we will use 120 volts moving forward. It will be less confusing.
120 volts has been “the norm” for almost 50 years and is somewhat the adopted standard these days. Just know the voltage can vary as much as 10%. The condition of the electrical system at campgrounds is a major contributing factor.
More on that in other blog posts!
For the sake of this basic discussion of your RV electrical system, we will lump together 30 amp and 50 amp service. They work the same overall and we will address the differences in a future blog post.
The 120 Volt Side of Your RV Electrical System
Purpose: The 120-volt system in an RV powers appliances and devices that require more energy. This includes things like the air conditioner, microwave, television, and wall outlets for plugging in other high-power devices.
Power Source: This system typically gets its power from external sources such as shore power (when plugged into an RV park’s electrical pedestal) or from a generator. When plugged into shore power, the 120-volt system provides the same type of electricity that you find in a standard home.
Operation: The power coming in is alternating current (AC), which is what most household appliances use. When connected to shore power, the electricity flows through the RV’s power cord into the RV’s electrical panel, distributing power to the various 120-volt circuits.
The 12 Volt Side of Your RV Electrical System
Purpose: The 12-volt system powers most of the RV’s essential functions and low-power devices. This includes the interior lights, water pump, vent fans, the control circuits for appliances, and sometimes the refrigerator.
Power Source: The RV’s batteries primarily power this system. The RV converter charges the batteries when you connect to shore power, run a generator, or use solar panels (if your RV has them).
Operation: The 12-volt system uses direct current (DC), while The 120-volt system uses alternating current. The fuse panel distributes DC power, ensuring each device gets the appropriate amount of power without overloading the system.
Key Differences in the 2 Sides of Your RV Electrical System
- Voltage Type: The 120-volt system uses AC (alternating current) power, while the 12-volt system uses DC (direct current) power.
- Applications: The 120-volt system is used for high-power appliances, while the 12-volt system is for low-power essentials.
- Power Sources: The 120-volt system requires an external power source like shore power or a generator, whereas the 12-volt system relies on the RV’s battery bank.
- Distribution: In the 120-volt system, power is distributed through breakers in the electrical panel. In the 12-volt system, power is distributed through fuses in the fuse panel.
Why Does My RV Electrical System Have 2 Systems?
Having both systems allows an RV to be versatile and functional both when connected to an external power source and when off-grid.
When you are parked out on a beautiful lake, the 12-volt system ensures that the RV can still operate its essential functions. Even when shore power is not available.
The 120-volt system provides the power needed for more demanding appliances. AC Power can come from shore power, a generator, or an inverter that gets it’s power from your battery bank. We talk about RV inverters in another blog post.
Understanding these two systems is crucial for maintaining your RV and ensuring a smooth and enjoyable travel experience.
We will talk about troubleshooting both of these systems in a future blog post, but this should get you started.
Have a great day and safe travels!
The difference between a 30 amp RV plug vs 50 amp RV plug is the amount of power your RV requires to power all of it’s 120 volt appliances. In general, the smaller or older RVs use 30 AMP outputs, while larger and newer RVs use 50 AMP outputs. You can immediately tell the difference between 30 and 50 AMP hookups because a 30 AMP plug only has three prongs and a 50 AMP plug has four prongs.
Your RV has both 120 volt AC wiring, similar to what your house uses and 12 volt DC wiring, similar to what your vehicles use.
The short answer is yes, but it will be VERY EXPENSIVE and a bit more complicated than that. Your RV air conditioner is a 120 volt appliance so you will need an RV inverter hooked to your battery bank and enough battery storage to power it all. We will address the expensive in other blog posts.
Yes you can because they are both 120 volt, but you will need an adaptor for either a 30 amp or 50 amp RV plug. You will NOT be able to run all of your appliance because a single house plug will likely be 15-20 amps tops.
There are several ways to power your RV without hookups.
1. Run a generator for 120 volts
2. Have solar power charge your batteries and run an inverter for 120 volts
3. Have a wind turbine charge your batteries and run an inverter for 120 volts
4. All your 12 volt appliances can run off a battery bank
Yes, your interior RV lights are all 12-volt and run off your batteries or the 12-volt power supplied by an alternative 12 volt source like a converter.