Greetings,

 

As I noted in my introduction here, being a boat owner has been a steep learning curve.  My current project is wiring and electrical.  In the bow of my boat, I currently have my 12v Minn Kota Terrova 55lb wired to a three prong marinco plug and receptacle, as shown below.

 

The power for the plug receptacle comes directly from the battery, and is fairly heavy gauge, I don't know for sure, but I would say probably 4 or 6.  I would like to wire my new Garmin Echomap Plus 93sv to this power source, and mount it in the bow.  Assuming this is feasible, what is the best and most professional way to accomplish this?  Thank you all for your time and expertise.

It is not a good idea to use your trolling motor battery for your depth finder.  Trolling motors cause lots of electrical interference.  It should be wired directly to your boat motor cranking battery.  Be sure to put the fuse that came with the depth finder in the line.

Exactly what Jig Man said.

 

Retired Grass Grower

As has been stated, it should be wired to the starting battery. Not sure what model your boat is, but if there's a panel with switches on it up front, many will have a power block you can hook them too. If not, I'd run new wires on the opposite side of the boat from the tm wires to wherever your starting battery is. 

You should run wire from trim switch fuse panel to the bow and add a trim rocker switch in the bow. The fuse panel should have cranking battery power for accessories, run wire to the bow from the accessory power terminal.

Tom

DO NOT wire your graph into the same power source as your trolling motor. Shouldn't even hook it to the same battery really. You will experience unreal amounts of interference. Run an independent set of wires or run a set of wires off your fuse block.

 

    Anything bigger than a 7 inch graph I would recommend 10 gauge wire. I had to upgrade my wire to 10 gauge with running two 7 inch graphs to fix a voltage drop issue I was having

21 hours ago, Jig Man said:

Be sure to put the fuse that came with the depth finder in the line.

on the + side and as close to the battery as possible.

 

On 6/11/2020 at 9:17 PM, Jig Man said:

It is not a good idea to use your trolling motor battery for your depth finder.  Trolling motors cause lots of electrical interference.  It should be wired directly to your boat motor cranking battery.  Be sure to put the fuse that came with the depth finder in the line.

Thank you for all of the great responses!  I appreciate everyone sharing their knowledge!  I am now planning on connecting it to my starting battery, as suggested.  I do not have a power block, so I will be connecting the power cable directly to the battery.  My new question is, does Garmin make a longer power cable than the one supplied, which is 6', or I going to have to run my own power cable from the battery to the bow, and then wire it to the supplied Garmin power cable?  I looked on Garmin's website under the accessories that were compatible with my device, and didn't find much.  The only power cable listed was the same length as supplied with the unit.

10-12 ga marine wire is the norm.