A solar panel wired straight to a battery will cook it. The charge controller is the part in between that decides how much current actually goes in, tapers it as the battery fills, and stops when it is done. 30 amps here, which is enough for roughly 400 watts of panel on a 12V system.

Two things make this one worth having over a cheap controller. It flush mounts, so it sits in a cabinet face or a panel where you can read it rather than being buried under the bed with the wiring. And it has an actual LCD display, which means you can see the battery voltage and what the panels are doing — the difference between knowing your system works and assuming it does.

Specs

• 30A solar charge controller
• LCD display — battery voltage and charge status
• Flush mount
• Manufacturer part number SCC-30AB
• Shipping weight: 1.45 lb

Bundle and save on shipping. Small parts like this ship in the same box as the rest of your order — add a few to one order and you pay shipping once.