I added a new to me graph on my boat and now have two larger graphs. They work great for a couple of hours but then turn off from low battery voltage. The battery still cranks the motor but the graphs will not work again until I charge the battery. What battery do I need to get so that I can run my graphs all day?

I recommend installing 10ga marine wiring for the graphs. I have upgraded the wiring in numerous boats for this very problem. Most of the factory wiring in my opinion isn’t sufficient enough to carry the current for the larger graphs. You may see up to two volts of drop from battery to graph = no good! I also am running the Odyssey 31 group Battery.

Might try two batteries. I use a Optima Grp 34DM on the motor and an Optima Grp 27 to run everything else. Three Carbons, Hydrowave, power poles, pumps, aerators, lights, Sonic Hub, etc.

I always had issues like yours, or worse, until I added the house battery. I don’t know what motor you have, but Yamahas have a dual, isolated, set of charging leads. It can charge a primary and secondary separately and without fear of one battery draining the other.

If you have the room and your boat won’t suffer too much from the weight, it is a good way to fish longer days.

Do this first. I had a problem with my front graph not working right, low voltage,and it was because of the wiring ,not the battery. I added 10 gauge wire to both graphs and that solved the problem.

I use a Deka Intimidator group 31 battery for my starting battery which also runs my electronics..

Odyssey pc2150 as stated is the best you can buy. No reason to add an extra battery and extra weight when you can get the Odyssey. It'll run as many pumps and graphs as you can install and crank your boat 10 hours later. It has 2,150 pulse cranking amps

Or buy a Dual purpose Lithium battery & get 8-10 years maintenance free service , 1250 CCA,100 Ahs, 24.2#’s, Eliminate the power issue for good. A win-win deal

Purchased 10 gauge wire today. Will let you know if that solves the problem. Much cheaper fix if it works.

Read your digital voltage on your graphs then check at the battery.

Sounds familiar. My side view doesn’t work and the graphs restart whenever I crank the motor. Sounds like this is my guide to fixing those problems.

I had to upgrade my wiring to keep graphs working when starting engine.i went to 6 gauge to fuse block and 10 out of the block.

Of course you want to do the correct gauge wire first, if it solves the issue. Yessir. Be SURE to use marine grade tinned copper wire though or you may have the same issue rear it’s ugly head again in 12-24 months. Good luck & hope that solves the problem

It worked on my graphs. I have a Lowrance 12 touch on the console and the same up front. The charts took way too long to load and the front one would just go off from time to time. Installing the 10 gauge wire fixed all of that. I located the fuses close to each unit.

+1 That will show you if you have a voltage drop to the units. I bet you do. I did on mine before I added the 10 gauge wire. Now they work great.

10 gauge wire and Interstate 31 AGM repaired all my problems.