How to Wire a Marine Battery Charger
Boating is exciting and fun as there are many things you can do on the water. However, marine batteries are either discharging power or they are recharging. There is no happy place between the two. So if you don’t want to be stranded out on the water with no power, installing a battery charger is an answer to the problem.
Items you may need:
- Water
- Baking soda
- Wire brush
- Heavy duty UL-rated extension cord
- 5/16-inch insulated wrench
- 3/8-insulated wrench
- Safety glasses
- Wear your safety glasses as you do this to make sure nothing gets in your eyes.
- Using the 5/16-inch remove, the nut on the black (negative) battery post and remove the battery cable. Whenever working on the batteries always remove the negative terminal first. (It will also be the last re-connected.)
- Remove the 3/8-inch nut on the positive (red) battery post and remove the red battery cable from its battery post.
- Mix three tablespoons of baking soda into a quart of water. Mix it in and clean the outside of the battery with the solution. It would be good to scrub both battery posts or perhaps sandpaper them in order to ascertain a good electrical connection when the cables are replaced.
- Put the 3/8-ring terminal from the battery charger over the positive post and place the positive battery terminal cable on top of it. Replace the nut and tighten down with the wrench.
- Place the 5/16-inch ring terminal on the negative post and cover with the 5/16-inch black cable from the battery. Replace the 5/16-inch nut and tighten down with the wrench as well.
- Plug the battery charger into your boat generator’s 120V ground fault circuit interrupt (GFI or GCFI) power outlet.
Should you be connecting to an electrical supply that is shore-based other than hard-wired plug your battery into a heavy-duty UL rated extension cord and then into the shore-based power source.