DEPTHFINDER WIRING

[TRRANGER]

Am inquiring as to the proper gauge wiring that would be needed to handle 2 humminbird units, 798 and 998, 2 other humminbird 788 and 1198. They will be wired direct to the battery running from the stern of the boat to the bow( 2 units ), and from the stern to the steering console ( 2 units ) in separate runs to each location.  They will be fused but not sure on amperage to use thinking 3 or 5 amp. Was thinking 16ga wire would handle it but wanted some input. The manual says 18ga and 3 amp, but I am running 2 units and the distance in an 18 foot boat was wondering if the heavier wire would be a better choice. Thanks for the help. TR.

[bfishn]

Engineering Toolbox has you covered;

http://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html

 

[Seth]

If you are running new wire, I would run 10 or 12 gauge to the bow to a terminal block for the two front units. Install a fuse on the positive wire at the battery (20amp for 12 gauge or 30amp for 10 gauge) and then wire your graphs to the power strip with a 3amp fuse on the positive wire between the fuse block and graph. The 3 amp is to protect the graphs and the bigger is to protect the main run. You could do the same for the console units, but it would probably be easier to just run those back to the battery with 14-16 gauge wire since they are closer to the bilge area.

That setup is overkill for the bow, but you will have room to add other devices to that power strip if needed in the future.