How do I Wire a Fish Finder Onto a Small Electric Boat?

A fish finder may make finding fish easier.

On the small electric boat, the battery not only provides power to the fish finder but to the electric motor that moves the boat. Series wiring, where the fish finder is connected to another instrument or to the motor, will maintain a level current--the number of amps(REF 2)--but Ohm's Law says the voltage available to the fish finder will drop because of increased resistance. The solution to this problem is a parallel circuit created by wiring the fish finder directly to the battery.

Things You'll Need

• Red copper stranded electrical wire, 16 gauge (AWG)
• Green copper stranded electrical wire, 16 gauge (AWG)
• Wire stripper
• Soldering gun
• Silver core solder
• Inline fuse holder
• Vinyl electrical insulation spray
• Adjustable wrench

Instructions

1. Strip the ends of the red wire and the green wire with a wire stripper. Use a soldering gun and silver core solder to solder a piece of red 16-gauge wire to an inline fuse holder. Cover the soldered joint with vinyl electrical insulation spray.

2. Use an adjustable wrench to remove the nut from the positive post of the boat's battery. Remove the battery cable from the battery post.

3. Connect the inline fuse holder to the power terminal on the rear of the fish finder. Set the battery cable terminal over the positive battery post. Wrap the stripped end of the red wire clockwise around the positive post of the boat's battery. Thread the nut onto the positive post and tighten snugly with an adjustable wrench.

4. Attach the wire from the fish finder's transducer to the fish finder's input jack. Ensure the fish finder is off. Insert the fuse into the fuse holder.

5. Attach one end of the green wire to the grounding terminal on the fish finder. Remove the nut from the negative post of the boat's battery, wrap the free end of the wire clockwise around the battery's negative post. Thread the nut onto the negative post and tighten snugly with an adjustable wrench.

Tips & Warnings

• The fuse chosen for the holder should be the same as the fuse used in the fish finder.

References

• NDT Resource Center: Ohm's Law
• Antoine Education: Series and Parallel Circuits