http://blog.rvshare.com/rv-solar-panels-everything-you-need-to-know/
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System overview: These are the main components, and may not include individual items needed for installation.
Panels: Along with the information above, they do come in various sizes, and you can even purchase additional ones, and add more later, without a whole system overhaul.
Charge controller: This controller is to regulate the flow of electricity to your batteries. You don’t want them to over-charge your batteries.
Battery monitor: This is great to keep track of your battery levels. They act just like a fuel gauge does to your gas tank. If you want to know exactly how many more amp hours you have, this is the monitor you need.
Inverter: To convert the DC power from the panels into AC power, which is used to power things like your coffee maker, phone chargers, vacuums and TV’s.
Wire harness: To carry the charge from the panels to the batteries.