How Does Your RV Electrical System Work
Whether you’re new to the #RVlife, or have had one for a few years, understanding how your RV electrical system works is a great way to keep your RV in top condition, avoid any electrical mishaps to your electronics/appliances/RV system, avoid electrical injuries, maybe do minor troubleshooting (or maybe even consider getting some modifications or upgrades), or help better explain to your RV Technician any problem that may need their expertise. I know this topic may seem daunting for some, but don’t worry, I’ll cover the basics and focus on some of the most asked questions.
Before we go into the nitty gritty stuff, I wanted to highlight electrical safety first because any electrical hazard (open wires, short circuits, etc.) can cause burns, shock and electrocution. There are a lot of safety tips online, but some of the most general reminders I’d like to share are:
Basic RV Electrical Terms
I’ll run through a few basic terms and acronyms we’ll be using throughout the article which will be helpful, especially if you’re new to this, or would just like to recall some of these terms you probably went through in school, but never really took it seriously, until now.
= daily watt hour consumption
= watts of the appliance x hours used per day
= watts of the appliance x minutes used per day ÷ 60 minutes
*Some appliances are only used for a fraction of an hour or minute per day. So if you need to compute for the Wh of a 1100W electric kettle for 10 minutes per day
I’ll be mentioning these terms a lot in the article, so if you get confused, don’t hesitate to go back to this section.
Overview Of An RV Electrical System
To keep things simple, your RV electrical system is made of both an AC & . The AC system, which connects to shore power, and the DC side, which is connected to your batteries. Your average RV electrical system will also have a breaker panel, a converter, one (or more) 12V batteries, lights and appliances that run on DC (12V), and/or also AC (120V).
An RV’s AC (Alternating Current) system
Before you plug in your RV, make sure the pedestal, your RV’s electrical system is off, and all appliances are switched off. Once that’s done, check the wiring of the pedestal & campground. Ideally, pedestals should include breakers, but just in case there isn’t, it’s always better to have a surge protector on standby, just to be safe, especially if there are power fluctuations. The surge protector will have indicator lights that show if there’s something wrong with the campground wiring, so it would be good to do this test before plugging your RV in. Others use a polarity tester, instead of a surge protector, so do use whichever is available in your area. Next would be to plug in your RV power cord. Once that’s secured, turn on the pedestal. Doing these precautionary steps helps protect not only your RV and all electrical appliances in it, but you as well.
As a side note, pedestal breakers are usually designed with a +/- 20% tolerance. So if a regular 30-amp outlet supplies 3,600 watts (30amps x 120v), the pedestal breaker could still trip between 2,880 watts and 4,320 watts (these values are the +/- 20% tolerance I mentioned earlier).
Once you plug in your RV to connect to shore power (AC), the flow of electricity goes as so:
Pedestal > (Pedestal Breaker) > (Surge Protector) > RV Breaker Panel > RV Converter> 12V battery bank & other 120V appliances
This flow would be similar if you plug-in your RV to a generator. Large RVs may come with a pre-installed propane-operated generator, but if you do want to purchase one aftermarket, we’ll discuss this later on in the article HERE.
An RV’s DC (Direct Current) System
When it comes to the DC system, although there are appliances on your RV that may run on propane, some of the items will still need to connect to DC power to get it started. Let’s compare this to your car that runs on petrol. It will still need to use the starter (which is connected to your car battery) to get it going. Examples of items on your RV that would still need a DC connection from either your converter or battery bank would be your fridge, furnace, water heater, lights, power outlets, etc. – which is basically almost everything.
We’ll not cover your RV and battery wiring in detail, since this is best left to your RV Technician, but I would like to mention thatyour DC system will also be affected by how your batteries are wired (if you have more than one), as seen below:
When it comes to solar and wind options, their system gets wired directly to the inverter/charger unit and your RV battery. We’ll discuss more of this in a separate section of the article (HERE).
What Is the Standard RV Electrical Hook Up?
The available RV electrical hook-up service, or pedestals, in an RV park or a developed campground would be:
Not all pedestals will always have the power service that you need. The most common pedestal plug-ins in RV parks would be a 30-amp service, but, for the sake of convenience, it would help if you always kept adapters (known as “dog bones”) handy so you could safely plug-in your RV, regardless of whichever service is available.
If you’re new to this, check your RV manual to know what amperage your RV requires for charging. Understanding how much power you need for your RV will help avoid unknowingly plugging your RV into the wrong pedestal outlet.If that does happen, it could trip your circuit breakers, probably destroy any appliances that’s plugged in or hurt someone (there’s a possibility of shock since your RV is made of metal, which can conduct electricity if touched).
Larger RVsusually require more electricity, due to the fact that it has more toys on it that need to be powered. If by chance that there isn’t a 50amp service available on the pedestal, you can still plug your RV into a 30amp outlet, but you’ll need to use less of your electrical equipment onboard (more on this in the next section of this article).If possible, use shorter adapters and extension cords, to avoid voltage drops.
Obviously, if you’re boondocking/dry camping, pedestals won’t be available, which is why solar panels &/or generators will come in handy in the event that you need to charge your batteries. We’ll discuss more about these optionslater on in the article.
Can I Plug My 30amp RV Into A 50 amp Service Without Damage?
Yes, you can plug in your 30amp RV system into a 50amp service using a 30 to 50amp adaptor. The adaptor will have a 120v 50amp male end with a 120v 30amp female end. This will not be the case if ever you plug in your 30amp RV system into a 220v 50amp Welder plug.
Can I Plug My 50amp RV Into A 30amp Service Without Damage?
Yes, you can plug-in your 50-amp RV electrical system to a 30-amp service with a 30amp male to 50amp female plug adapter, but remember that the service decreases to 30amps. This means you either won’t be able to use all your appliances onboard at the same time, or, if ever you get some of them to work, you may be risk damaging these items as they operateon substandard power. This could be more expensive in terms of repairs or even replacing the unit).Let’s say you’re not running the power-hungry items all at the same time (e.g. RV fridge, heater or air conditioner), and keeping electrical appliance use to the minimum, you’ll hopefully be fine.
One more thing I want to add,if you’re plugging your 50-amp RV system into a 30-amp service, and there are other 50-amp RV’s also plugged in as well in the same campground, it will affect not only the other 50-amp RVs, but the 30-amp RVs as well.
Can I Plug My 50amp RV Into A 50amp Service Without Damage?
Yes, you ideally should plugin your RV with a 50amp electrical system to a 50amp service. As recommended by a technical advisor, this helps protect the long-term dependability of the appliances onboard your RV, plus this shows consideration to the other RV campers since you won’t be tapping into the 30amp service supply for your 50amp RV system.
Can I Plug my RV to my House to Charge Before Going on a Trip?
Yes, you can. In fact most people will automatically charge their batteries as they plug in their RV fridge to AC power to cool it down for about 24 to 48 hours before loading it full of food. This action automatically charges the RV batteries in that time.
How Does an RV Converter Work?
Your RV Converter works very similarly to a battery, but it is designed to convert AC power (110-120v) to DC power (12V), and stay plugged in for long periods of time, or short stays. It also has a voltage regulator that will help keep the power consistent as it charges your batteries (and, if it works properly, it won’t overcharge them).
Most converters usually have 2 charging stages, but the bigger (and more expensive) ones would have a 3rd stage. These charging stages are:
Depending onyour converter’s manufacturer, the converter’s BULK mode can take the battery to 14-14.8 volts, FLOAT mode can take the battery up to 13.2 volts, and if it has an ABSORBTION mode, your battery can hold up to 14-14.8volts for a few hours, before going to FLOAT mode.
How Much Power Do I Need for My RV?
To determine how much power you need for your RV, you’ll need to diligently list down everything, and I mean EVERYTHING, that consumes power in your RV. Also take into consideration how much power exactly each appliance needs, if you’ll be using all these appliances at the same time, and also how long you’ll be using it. An example of this would be if you’re running your RV fridge, together with your AC or heater, while the lights are on and you’re charging your phone, while someone watches TV and/or someone else needs to use a hairdryer. Also note that there are appliances that take awhile (and more power) during start up, and will drain more power before it stabilizes and runs on its average power consumption per hour.
As you’re listing down all the items that require electricity, there should be a label on the unit (usually in the back, or underneath) that will show the rated voltage &maximum amperes it needs to run. Some labels will also include the watts (so you don’t need to compute for it). Following the formula to compute the wattage will help get exactly how much electricity you need. This will help you:
If ever you do just want a guestimate on how much power you need for your RV, below are examples of the approximate wattage of certain RV appliances.
|Appliance||Start-up Wattage||Running Wattage|
|Basics||RV Rooftop Air Conditioner (13,500 BTU)||2800-3000W||1500-2000W|
|RV Rooftop Air Conditioner (15,000 BTU)||3300-3500W||1300-1800W|
|Furnace Fan Motor (1/3HP)||–||1200W|
|Electric Water Heater (6 gallon)||–||1200W|
|Power Converter (780W)||–||780W|
|Water pressure pump||–||50W|
|One (1) LED Interior Lightbulb||–||8.5W|
|One (1) Incandescent Lightbulb||–||60W|
|Kitchen||RV Refrigerator (small)||600W||180W|
|Electric Kettle (1100W)||–||1200W|
|Bathroom Vent Fan||–||12-35W|
|Other Electronics/Appliances||Small Flat TV||–||120-200W|
|Mobile phone (charging)||–||3.68W|
|Hair Dryer (1600W)||1900W||1800W|
These are averages, and the list could go on, but I really would recommend doing the work, so that you get to know your RV’s electrical load properly. This will also allow you some leeway if you want to upgrade your electrical system, your RV interior light bulbs or appliances.
What are the Different RV Batteries Available?
Deep cycle batteries are used more often for motorhomes/RVs, solar power systems, boats, etc. but they’reoften marketed withterms that are often interchanged. So, when it comes to the world of deep cycle batteries, the available types are:
I have a separate article explaining this in detail (HERE), sinceeach of these deep cycle batteries have their pros and their cons.
What is a Motorhome Inverter?
An inverter converts the direct current from your 12v batter into a 120v alternating current. When you’re boondocking, your batteries will automatically power all items that run on DC power. Adding an inverter will allow you to use your electrical outlets and all other 120v appliances (provided you’ll have enough power stored in your batteries).Small inverters, like a 3000 unit, can even handle the easy start of small factory AC units. You can read more about it here.
How Do I Set Up a Solar Power System for your RV?
Especially if you’re boondocking, having a RV solar power system is a convenient, clean and eco-friendly way to get the power needed to charge your batteries off-grid. Provided it’s sunny, you have a modest sized battery bank of 200-300AH, a small to medium sized power inverter, and a modest sized solar panel array of 400-800W.
Setting up a solar power system for your RV will highly depend on your short and long-term goal(s), and your budget, since the upfront costs of setting one up can be quite expensive.
Whether you set it up by yourself, or get assistance from your RV Technician (especially if you’re not too familiar with your RV’s electrical system), you’ll need to determine (1) your budget, (2) how much power you need (which I mentioned already in an earlier part of this article HERE ), and (3) how big your battery bank should be (including the weight limit and amount of storage space you’re allotting for the batteries). Once you have the answers set, then finding the best suppliers for your solar panels, cables, batteries, etc. will be the next step, since the limiting factor here will be your budget (and maybe time, if ever you’re in a rush to set it up). If you’re more comfortable with working with electricals, it is possible to do this on your own, but if not, I would recommend that you consult or have your RV Technician help you set this up.
Assuming you’ll be parking in areas that get a lot of sun, the flow of electricity would follow:
Solar panels >charge controller* >battery bank > inverter > AC system (*prevents overcharging)
Maintenance for a solar power system is low, since you’ll just need to clean the solar panels 3-4x a year (depends on how dusty/dirty they get), and might as well just double check the wiring and your battery bank (since there are some batteries that need more maintenance than others).
Generators for RVs
Generators are great for powering appliances that require a lot of electricity, like air conditioners, microwaves, hair dryers, etc. If you’re deciding to get one, they can get expensive, and so is running them for long hours (not to mention the noise and fumes it’ll create), but they will be a lot cheaper than in the short term, as compared to a solar panel setup.
I mentioned earlier that some larger RVs already come with one pre-installed, so if you’re buying one after market, similar to the solar panel setup, you should have a clear idea on (1) your budget, (2) how much power you need (which I mentioned already in an earlier part of this article HERE), and (3) how much storage space you’ll allot to the generator and the petrol you’ll use.
Maintenance and Care of your RV batteries
Each product will have different maintenance and care instructions, so it’s always to follow it. Since we’re covering your RV electricals, below are some general tips you can follow to keep things in tip top condition:
There are more, but if in doubt, you can always check with your RV Technician if you have any concerns.
We’ve covered some general safety tips, the overview of your RV Electrical Systems, and some of the frequently asked questions when it comes to this topic. Electricity is no joke, and can cause harm if not managed properly, so understanding it brings nothing but a good working knowledge of how to maintain and operate your RV properly, and keep you and your loved safe.