Boat Wiring Basics


Last February I bought a Columbia 22′ sailboat. I have only used the boat for daysails so far, and have never required any electrical systems. However, I’d like to wire up the basics (navigation lights, cabin light, VHF radio) and power it through solar power, if that’s possible.

The boat came with a battery (Group 24 I believe), a new electric panel (with wires and fuses) and a whole lot of red and black boat wiring running around the inside leading to holes where the previous owner had been preparing to install navigation lights and cabin lights. I haven’t touched the electrics since I bought the boat (mostly out of fear and never having done anything with electrical systems before). I’d be THRILLED if I could just get a single cabin light working … but I don’t really know where to start.Columbia 22 Sailboat Group

What kind of tools do I need? Should I pull out all those other wires and just start fresh? What should my first step be?

Please – I’m very motivated to start this project … I just need someone to point me in the right direction.



Hi Adam,

Here are some basics that you will want to follow:

  • Each electrical part that you install will need to have a power and ground wire that can handle the current of that device.
  • Each power wire needs to have circuit protection (fuse or breaker) that is sized for the device.
  • The switch panel feeding these devices needs to have a power and ground wire connected to the battery that need to be sized to handle the current requirements of the panel.
  • The power lead for this panel needs to have circuit protection as close as possible to the battery.

Using a 12 volt meter, some wire connectors, and some wire crimpers, you should be able to get all of your devices working. Pay attention to wire size and current draw of each device to make sure you are not under sizing your wire which can lead to overheating and fires. You can use my boat wiring size calculator to determine if you have the correct wire size.

Another option is to buy a pre-assembled new harness and panel that would just plug together. You would spend less time wiring and more time boating.

My partners at EzAcDc have most of the marine electrical parts that you would need – most on their closeout page.

Hope this helps. Please let me know if you have any questions,