Using A Battery Charger On RV Batteries
Sometimes you might need to charge your RV batteries with something other than the converter inside your RV.
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Charging with solar panels is the most common type of external RV battery charger that’s used but you can also connect electric deep cycle battery chargers.
Solar panels that can charge batteries are a great way to keep your RV’s electrical system running when boondocking.
Since it’s often recommended to disconnect your RV batteries when your RV is plugged in for a long time using an electric battery charger is a good way to keep the batteries healthy when you’re not using them.
The same concept goes for winterizing your camper and storing RV batteries.
Where To Connect A Charger To RV Batteries
RV battery banks vary a lot. Many campers have different kinds of battery setups depending on the kind of camping they do and personal preference.
You can have multiple 12 volt batteries wired in parallel, 6 volt batteries wired in series or just one 12 volt battery that’s only meant to supply the RV with enough power to camp for a night.
It’s not always obvious where you should connect the battery charger but it’s easy to figure out if you know what to look for.
In most cases, you always want to charge from the same battery terminals that are being discharged.
That means you should connect the charger in the same spot as the RV load wires.
It also doesn’t matter if you’re connecting a solar charger or an electrical one. They both work the same way when it comes to wire placement.
The biggest reason you should connect the charger to the same terminals as the load wires is because the load wires will be placed in the best possible position to draw equally from all of the batteries in the battery bank.
That means if you place the charging cables in the same spot the batteries will also be charged equally.
Common RV Battery Connection Questions
Which Charger Cable Should I Connect First?
When connecting wires to batteries the rule is to always connect the positive first and then the negative.
When disconnecting remove the negative first and then the positive.
Is it ok to use a trickle charger on an RV battery?
You can use a trickle charger on an RV battery but there are a few things you need to think about before you do.
First, making sure you have a trickle or battery charger that’s compatible with the type of batteries your RV uses is going to be the most important.
If you have Lithium batteries you are going to need a charger with a setting specifically for Lithium.
There’s some discussion about using a trickle charger on an RV battery while the RV is connected to power so the converter is charging the battery as well.
It seems to greatly depend on the chargers themselves. Sometimes it works to use two at once but sometimes the current of the other charger will keep the charger from charging the battery.
For the most part, it’s not really recommended since you don’t have much to gain from it.
If you want to charge your RV batteries with an external battery charger without having to unplug your RV or unhook the RV wires you can always turn off the converter so only the external battery charger is charging the batteries.
The switch for the RV battery converter is located inside the RV breaker box. It’s usually labeled “converter”.
Can solar chargers be used while the RV converter is on?
In most cases yes. Solar charge controllers are usually intelligent enough to be used at the same time as the chargers built into RVs.
You shouldn’t have to disconnect your solar panel charger from the RV batteries whenever you plug in your RV.
Have any more questions about where to connect the charger on an RV battery? Leave a comment below.