Understanding how your batteries and your 12 volt power system work is important for trouble free RVing. Maintaining your RV batteries will keep you from replacing them prematurely and can save you time and money for unnecessary repairs. Make the most of your power usage and maintain those expensive batteries for trouble free travel. This quick guide will keep you powered up!
Quick Guide to Power Usage in Your RV
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AMPS & Watts
If you have a 50 amp rig you have as much power as your need and probably don't have to think about your usage very much. As you travel place to place, you may run into a situation where 30 amp power is the only power available. That’s not normally the case in RV Parks, but it does often happen in state park campgrounds. There is a big difference between an RV 50-amp service and an RV 30-amp service – 8400 watts to be exact. The 50-amp service uses two hot legs at 50 amps each while the 30 amp service uses one hot leg at 30 amps. This is important to know if you ever have to plug your 50 amp service into a 30 amp receptacle using an adapter. If you ever need to do this, you will need to scale back power usage significantly. You will only be able to run 1 A/C and a few other appliances. You will need to watch your wattage usage carefully and plug and unplug things as you need to use them.
RV 50 Amp Service = 12000 Watts RV 30 Amp Service = 3600 Watts
The chart below is to help understand how much you can run on a 30 amp service. Remember, there are a lot of smaller appliances (cell chargers, laptops, TVs, etc.) that may already be plugged in that can add up to a large amount of wattage consumed. Knowing what is plugged into each circuit can help you determine why your RV breakers are tripping,
The chart below is only a guideline; the exact wattage usage can vary a lot depending on the specific appliance. You can easily calculate wattage usage yourself. To calculate wattage, you need two things: POWER which is 120 volts and AMPS. All appliances are labeled by the manufacturer with a power requirement label somewhere on the item. Look for the input voltage which is most likely 120 volts and amps, or amperage can be any number.
- My laptop power charger has an input voltage of 120 and it draws 1.7 amps, multiply 120 x 1.7 = 204 watts.
- A bender has an input voltage of 120 volts and draws 10 amps 120 x 10 =1200 watts.
We have included a voltage reference chart in THE COMPLETE RV TRAVEL PLANNER for your convenience when you are on the road. This chart gives you average numbers for most items you may find in your RV. Remember, to check the manufacturer labels on your appliances if you are in doubt. They already provide the number of watts printed on it the bottom or the tag for your convenience. Just add them up and see what you can run at the same time.
Your wattage can add up fast. So if your breaker trips, it may be that you are overloaded. Turn off one or two things until you have solved the problem.
Batteries are one of the most important component in our RVs. RVs depend on a strong battery bank to power things like inverters, pumps, slides, electronics and TVs. Keeping our batteries properly maintained is one of the most important things we can do to help eliminate many of our RV problems.
CAUTION: When handling batteries, electrolyte, and charging your battery always wear protective clothing, gloves and goggles.
Battery Inspection Checklist
- To keep your batteries working at their optimum levels do an inspection of them monthly using this process:
- Examine the outside look for cracks in the container.
- Check the battery post and connections – they should be clean, tight and corrosion free.
- Check battery cables for damage or fraying (replace any bad cable)
- Make sure no fluids (electrolytes) have spilled, leaking or leaching out (leaking batteries must be replaced)
- Make sure batteries are matched set (same type, age and make) a miss matched battery can weaken or destroy your battery bank. Batteries must be replaced as complete sets.
- Check Voltage – All Lead-Acid batteries supply about 2.14 volts per cell (12.6 to 12.8 for a 12 volt battery) when fully charged.
How to Clean a Corroded Battery Post:
- Be sure to disconnect battery (batteries) before cleaning. Undo the negative and then positive cable attached to your battery. (Turn to your owner’s manual for help on this part.)
- Mix 1 tablespoon of baking soda with 1 cup of very hot water. Use an old toothbrush to add the mixture to the corroded battery post and cable ends. Scrub the top of the battery to remove the corrosion You can even dip the ends of the battery cables in hot water to dissolve any corrosion on the cable ends themselves.
- After battery post and cable ends are clean wipe dry with disposable clean rag and reattach starting with positive and then negative cable ends. (Turn to your owner’s manual for help on this part.)
- Apply petroleum jelly or anti-corrosive spray to help protect terminals (can be found at any local auto parts) help prevent further corrosion, and help strengthen the connection
How to Check the Water Level:
If the electrolyte levels in the cells are low (plates are exposed), fill each cell to just cover the plates. Use only distilled water to fill the cells. Distilled water can be purchased at most grocery stores. Be sure to use a battery watering system and make this job easier.
How to Charge Your Batteries:
To charge your batteries simply plug your RV into shore power or run your generator (if you have one). If your batteries are depleted or low, recharging them may take a few hours.
How to Check Battery Voltage:
While plugged in to shore power with converter working, you should have a battery voltage of 13.7 volts. Your RV will may already have a battery voltage meter, if not you can use a Multimeter. This will indicate your converter is working properly. When your batteries are fully charged, disconnect shore power and recheck voltage. You should see 12.6 volts and above.
Knowing about your rig, all the RV systems and maintenance to do is overwhelming. So we created more content to help you as you use and have fun in your RV.
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- Need help to know if that used RV you are considering buying is mechanically sound? See why an Certified RV Inspection might be good for you!
- Have an AquaHot? Read 10 Important Things You Should Know About Your AquaHot .