RV electrical systems are the heart of the house and they are responsible for running all appliances, lights and electrical components. The RV engine operates an electrical system separate from the house but the house battery and shore power systems are the primary focus here. These are the systems that run everything outside of the mechanical engine and every wire, fuse and connection is critical to the functionality of the camper.
12V and 120V Systems Basics
Most RV and travel trailers run on both 12V DC and 120V power. The 120V runs the big things like a refrigerator and air conditioner. These power heavy appliances require a steady current and they will drain batteries in a hurry which is why they most often operate solely on shore power connections. Refrigerators can continue operating off grid on propane gas in most situations as well.
The 120V coming from shore power will convert to 12V DC for the operation of small draw components like a water pump and overhead lights. The house battery also operates all 12V DC components but it will not send power to the big items like Air Conditioning. This means you can operate off-grid with the 12V power on a charged battery.
Running Off Shore Power
Shore power is ideal for operating the RV like a house. The refrigerator will run on electric and air conditioning is available for use in hot weather. Shore power is connected to a 30 amp, three prong plug in most cases and it supplies a steady stream of power for the entire house. The shore power will run all house systems while keeping the battery topped off as well. Shore power is also an option with a regular extension cord when run to a house outlet. The extension cord will connect to the 30 amp plug through a common adapter. These adapters are readily available online, at RV stores and dealers and even through hardware and retail stores.
Battery Charging and Maintenance
The battery or battery bank is critical for operating off-grid. Most RVers using regular shore power connections will only keep a single deep cycle battery to run for a short period of time off-grid. Full time boondockers will utilize a battery bank in many cases to ensure the power is always available to run lights, water and the necessities. You can even run a coffee pot and fan off the battery without any issue.
Batteries are best used when fully charged and deep cycle batteries are the best option as they handle charge and discharge cycles better than batteries designed for cold cranking to start a vehicle. The deep cycle batteries do however work best when only discharged to 50-percent before being recharged again. Dipping below a half charge will wear out the battery quicker and it will eventually struggle to hold a charge and require replacement. Put a trickle charge on batteries while parked to keep them topped off and ready for use. Set up an inverted or warning system to shut down power when the battery bank is discharged to 50-percent as a safety measure as well.
Solar systems are ideal for charging batteries while boondocking. Solar panels are easily mounted to thr roof or used in folding styles that set up on the ground. The solar panels are then connected to a controller that regulates the flow of electricity to the batteries while charging. The charge controller is a critical element and inspecting the connections to ensure the unit is functioning is very important. When the camper is parked in full sun. do a daily check to see if the controller is delivering energy to the batteries. A simple, loose connection can cutoff the charging and drain the batteries. Make sure the connections are tight and the controller is reading while charging.
Common electrical issues include blown fuses, loose connections and broken wires. Wires can be cutoff by rodents or accidental pulling and all terminal connections are important for normal function. If the power cuts off and you know the batteries are charged or you have shore power, start with a basic observational analysis.
In many situations, the power will only cutoff at a single outlet and this frequently happens because that outlet is overloaded with too many appliances. Use a surge protector when running multiple items of a single outlet simultaneously. If the single outlet does cutoff, it’s a surge protection feature. Press the surge button if available on that specific outlet to reset.
Fuses will also blow on occasion. Become familiar with your breaker box and fuse panel to quickly diagnose issues. Oftentimes, replacing a fuse or flipping a breaker will solve problems in a matter of minutes. If the fuses and breaker levers are not the issue, inspect the individual wires from the source of the issue, back to the breaker. Look for broken wires and loose terminal connections to locate the point of necessary repair. Always shut off the electricity completely while performing these tasks as a primary safety measure.