Portable Generators are quite popular among homeowners and small businesses that suffer from frequent power outages. Even if there are no blackouts in your area, these generators are very useful during emergencies such as hurricanes, storms, blizzards, etc. During these times, it becomes very difficult for utility companies to supply electricity and portable generators act as a backup until the grid is restored. Another major use case of portable and mini generators is camping, especially cross-country traveling in RVs and Motor Homes. As you spend weeks or months in RVs, you try to include everything in them to make it feel like home. These include both electrical and non-electrical items. Speaking of electrical items, RV owners design the electrical system in such a way that it could run all the electrical appliances from multiple sources of power.
A simple way to do this is to take a single large service and connect it to all the outlets inside the RV. One such common “service” in RVs is a 30 Amp Plug. Most modern and even some older motor homes have 30 Amp electrical service and you can power it through shore power, generators, and solar. If you are planning to purchase a generator to take it in your RV, then the important question is what size generator for a 30 Amp RV Electrical System?
In this generator and RV Guide, let us understand the basics of the RV Electrical System, the importance of a 30 Amp Plug or Service in RVs, different ways to provide electricity in an RV, and also the size of generator you need for a 30 Amp RV Plug.
Introduction
We take electricity for granted in our homes and offices. In fact, we cannot imagine a day going by without electricity. The alternating power that we have in our homes is one of the cheapest and easiest to produce. As a result, most of our appliances, be they large as refrigerators, air conditioners, etc. or small as coffee makers, laptop chargers, etc. run on AC Mains Supply.
The reason we are bringing this up is nowadays, many of us are interested in traveling in RVs, campers, and motor homes to explore different parts of the country.
If we want to use any of our electrical appliances in an RV, then it becomes slightly difficult as they run on AC Mains supply (which is 120V 60 Hz in North America) and how are we supposed to provide that in an RV?
It is not as difficult as one might think because most modern RVs come with a 120 V AC Electrical System so that we can plug all our appliances into different outlets that are identical to the ones we use in our homes.
Even if your RV doesn’t have a factory-installed AC Electrical System, it is very easy to design and implement your own electrical system in the RV, provided you follow all the rules, regulations, guidelines, etc. while making such complex installations.
Basics of Electrical System in RVs
If you are an RV Owner, then you already know the essential parts of a typical RV Electrical System. But if you are a beginner, a first-time RV Buyer, or planning your first RV purchase, then understanding how the electricity flows in your RV is very important.
We can divide the electrical system in an RV into two types. A 12V DC System and a 120V AC System. Further, the 12V DC System can be divided into 12V Chassis System and 12V Coach System. Let us briefly see about all these systems. If you are interested, we can make a dedicated beginner’s guide on the entire RV Electrical System.
12V DC Chassis System
The first and most important electrical system in any automobile (cars, RVs, trucks, etc.) is the 12V Starting System. A battery, commonly known as SLI Battery, provides energy to crank the engine. Apart from this, it is also responsible for the ignition system of the vehicle, lighting, cabin air conditioning, stereo, etc.
Once the battery starts the engine of the RV, the alternator of the RV kicks in and supplies electricity to some parts of the car and at the same time, it also charges the Starter Battery.
12V DC Coach System
There is another 12V DC System in RVs and it is separate from the previous “Chassis System”. In this system, we have one or more 12V Deep Cycle Batteries in the “Coach” part of the RV that help in running lighting, fans, and other 12V DC Electrical and Electronic devices.
Apart from running 12V electrical devices, you can use a 12V DC to 120V AC Inverter and run household AC appliances as well (here AC means alternating current). Hence, the Coach Power or Batteries are sometimes known as House Power and Batteries.
An important point here is that the coach batteries are separate from the Starter Battery. There will be usually only one Starter Battery under the hood (near the engine) but you can find a bank of Coach batteries that are in the deep cycle category.
Another difference is the alternator starts the Starter Battery once the engine starts. This is not the case with house batteries. You could rewire the alternator of your RV to charge the house batteries as well.
Or you need to install a special charger (a combination of inverter charger is quite common) to charge these batteries either from the shore power or a generator.
120V AC System
Speaking of shore power and generator, the next electrical system of the RV consists of 120V AC Power. Similar to a residential electrical system, the 120V AC system in the RV has a distribution panel, circuit breakers, outlets, etc.
The input to the main breaker panel can come from shore power i.e., directly plugging it into an appropriate receptacle available on the campground or RV park. Another way to supply AC Input to the RV’s main breaker panel is by connecting it to a generator.
Depending on the size of the RV and its power requirements or handling capabilities, the input of the distribution panel can either be a 30 Amp plug or a 50 Amp plug. Usually, the RV side of the AC inlet is the plug (male with prongs) and the receptacles on the campground or generators are ports (female with slots).
Apart from these two, slightly older RVs have the regular household 120V 15A or 20A inputs. But these are becoming less common nowadays as power consumption is on the rise and there is a limit to the amount of power you can draw from a 15A or 20A outlet.
What about Solar?
Yes. We haven’t forgotten about the almighty solar power system. For a true off-grid living experience, you can install Solar Panels on top of your RV. Solar Panels fall under the category of DC Power Systems.
As the power requirement of an RV is slightly less than that of a house, you only need 12V Solar Panels. But keep in mind that you can get Solar Panels with higher voltage ratings as well (which are quite common for residential and commercial applications).
The advantage of Solar Panels is that you can either directly use the power from the solar panels with appropriate regulators and controllers or charge the Coach Batteries.
A Brief Note on the 30 Amp RV Service
The 30 Amp Electrical System is relatively common in small to medium-sized motor homes, RVs, and campers. It is a 120V system. So, when you combine 120V and 30A, the maximum power you can get from a 30 Amp RV Plug is 120V × 30A = 3,600 Watts (W).
This means the main distribution panel or breaker panel in the RV has a 30 Amp main circuit breaker. From here, we can run several 15A or 20A circuits with individual circuit breakers for different parts or devices of the RV.
As we mentioned earlier, the RV Side of the AC Input Power usually consists of a 30 Amp Male Plug of type NEMA TT-30P. On campgrounds and generators, where we connect the RVs inlet, is usually a 30 Amp Female Receptacle of type NEMA TT-30R or sometimes L5-30R (the locking type receptacle).
So, in order to connect the RV to the campground or a generator, you need a 30 Amp female (which plugs on the RV side) to a male (which plugs on the campground or generator side) type cable.
What Size Generator for 30 Amp RV?
In the previous section, we briefly discussed the power capabilities of a 30 Amp RV Electrical System. If you are planning to buy a generator for your RV and wondering what size generator for 30 Amp RV Electrical System, then this power rating becomes crucial.
The maximum theoretical power you can draw from a 30 Amp RV Plug (which of course is the size of the main circuit breaker in the RV) is 120V × 30A = 3,600 Watts (W).
So, while choosing a generator, make sure that it can deliver at least 3,600 Watts if you want to draw maximum power from your 30 Amp RV Plug.
However, depending on your power requirements and the number/type of device or appliance you want to plug inside your RV, you can get a generator with a power rating of anywhere between 2,000 Watts to 4,500 Watts.
There is no real advantage in getting a higher power generator, say a 5,000-Watt or 7,500-Watt Portable Generator. You are anyhow limited to a maximum power draw of 3,600 Watts.
If you purchase a higher power generator (with a rating of 5,000 Watts or more), you are unnecessarily spending extra money for the extra power that you are not going to use.
Also, as the power rating of the generator increases, its size and weight also increase proportionally. So, by purchasing a higher-power generator than what you need you are essentially adding additional weight to carry.
But if you choose a generator in the range of 3,500 to 4,000 Watts for a 30 Amp RV plug, it is perfect in terms of size, power capabilities, and also cost.
Keep an Eye on Starting Watts
While the power rating of the generator is the main priority while purchasing a generator, you need to be aware of the Starting Watts and Running Watts of the Generator.
For a 30 Amp RV Electrical System, the 3,600-Watt power we mentioned earlier is the maximum it is capable of handling. Anything beyond this, the breaker will trip.
So, the total power consumption of all the appliances you want to run inside your RV, including the highest of Starting Watts rating of all the devices must not exceed 3,600 Watts.
So, while choosing a generator, make sure that the Starting Watts of the Generator is at least 3,600 Watts (slightly above this value is good). In this way, you can be confident that the generator can deliver the maximum power your RV needs even in the worst-case scenario.
Popular Generators for 30 Amp RV Electrical System
Now that we have seen the basics of the electrical system in modern RVs and also understood what size generator you need for a 30 Amp RV Electrical System, let us take a look at some popular generators that fall under the category of “30 Amp RV Electrical System”.
| 30 Amp RV Generator | Running Watts | Starting Watts |
| Westinghouse 4650-Watt Portable Generator | 3,600 Watts | 4,650 Watts |
| Champion Power Equipment 201052 4750/3800-Watt Dual Fuel Portable Generator | 3,800 Watts | 4,750 Watts |
| WEN 56380i Super Quiet 3800-Watt RV-Ready Portable Inverter Generator | 3,400 Watts | 3,800 Watts |
| DuroStar DS4000S Portable Generator | 3,300 Watts | 4,000 Watts |
| Generac 7128 GP3500iO 3,500-Watt Gas-Powered Portable Generator | 3,000 Watts | 3,500 Watts |
| A-iPower Portable Inverter Generator | 1,600 Watts | 2,000 Watts |
Note that the generators we mentioned in the list are mere suggestions. We strongly recommend you calculate the power requirements by taking the Running Watts and Starting Watts of all the appliances that you want to run.
No matter which “30 Amp RV” generator you choose, make sure that it has the 120V 30 Amp RV Receptacle.
Conclusion
The number of people investing in RVs or Motor Homes is increasing year after year. Earlier, RVs were seen as homes on wheels for retired persons. But things are different nowadays as even the younger generation is ready to explore different parts of the country in an RV.
To make it feel like a true motorhome, RV owners customize the interiors of their campers with sofas, refrigerators, cooking areas, TV, bed, air conditioner, etc.
There are several ways in which you can power the electrical and electronic appliances inside your RV. The simplest way is to connect the RV’s electrical system to shore power. For this, most small and medium RVs come with a 30 Amp RV Plug and you can simply connect a proper cable to this plug and a receptacle on the campground or RV Park.
Alternatively, if you don’t have access to shore power, then a portable generator is the next best thing. As the 30 Amp RV Plug supports a maximum power of 3,600 Watts, you can select a generator that falls in this power category. You don’t have to spend extra and get a large generator as you cannot use that power with a 30 Amp RV Electrical System.
In this guide, we saw the basics of Electrical systems in RVs. We saw both 12V DC and 120V AC Systems.
Then we calculated the power rating of a 30 Amp RV Plug and understood what size generator for 30 Amp RV Electrical System. We hope that this guide could help you understand the basics of the electrical system in an RV and also how to properly size the generator in case of a 30 Amp RV Plug.
If you feel we missed something or want us to add anything, do let us know in the comments section below. It will not only help us but even other readers.
