What battery needed for a 7" screen fish finder...

I have aquired a new Garmin Striker 7 SV. It is recommended a Group 27 deep cycle battery. Has an inline 30a fuse. Can't remember for sure. Think it said 42a....

Anyway the two leads that go to the power source, the battery are way small. I can't wrap my head around a unit needing that much battery and have such small power wires.

I need to sort of keep weight down in my little 14' v boat. I think it recommended to not run it off the same battery as the foot control troll motor. Well I need a fairly big battery for the trolling motor. I really would like to get by with as small a battery as possible for the fish finder.

I would appreciate any advise or suggestions from anyone. Anyone who has had this experience and kind of knows what battery I can get by with would be a big help to me. I think it said a 105 ah battery recommended. I have a smaller 35ah I think I will try. Heck...can't hurt...much. I use said 35ah to run a 34lb trolling motor on my little 8' foam filled boat! Don't see why it would not work for the fish finder.

BTW.....if anyone is interested....I am thinking about selling my 8' boat. It fits down inside a long bed pick up with the tailgate closed. I have a 34lb thrust trolling motor on the front and a 1.5hp Evinrude Mate outboard on the back. Thinking about $400. Cost me a lot more than that to put it together. Anyway if anyone around Belfast Maine can see it in my front yard....actually in Waldo, about 6 miles inland from Belfast. Actually have a Bottom Line Fishing Buddy 4000?. Might sell it for a tad more with the boat. I bought it new at Cabelas and it cost me $234 plus tax.

uh.....sorry....uh....any help would sure be nice....

jim
yes, I know there is such a thing as a comma, creatures of habit.....duh...my touch typing habits.......

There is no way a fish finder needs a group 27 battery. I run my, admittedly, smaller less powerful finder off of a small sealed lead-acid battery like this:

https://www.amazon.com/UB1250-Sealed...ub1250+battery

I'd look for a larger battery for your Garmin. It depends on how you are going to use it. How many hours a day do you use it? Can you charge the battery at the end of the day? The specs for the Striker 7sv says it draws .67A .

Jay is right. I have used a smaller group 24 to power both a 36 lbf trolling motor and a sonar. Their warning about not powering the sonar off the TM battery is the possible electrical interference (noise) you could get if they're both running. But try it and see - may work fine.
Other than that, the 5 ah gel cell he recommended is also a good choice. I have a 12 amp-hr that will run a sonar for days. BUT, you have to be able to charge it with a "smart" charger - one that senses charge level and tapers back when it's charged. Same with your 35 ah TM battery, BTW. Just get some connectors at a Walmart that fit the gel cell and splice them to the sonar power leads.

Very grateful for the information from boaf of you. I was fooling with a Minn Kota AT 40lb foot control motor at the same time. I might of mixed up my info. But the Battteries Plus guy I consulted said it calls for a Group 27 also. So my suspicions were pretty good. Don't need way near that. I have a Duracell Ultra....uh...model DURA12-9NB which says it is a 9AH AGM battery. It is only about 6" long x 2.5" wide and about 3.5" high. 'methinks with the information you guys have provided I can do just fine with it.. Bought it a couple of years ago at Batteries Plus and have not used it, but kept it charged. I do have the ability to charge batteries every night if needed. When I was telling the Batteries Plus rep I needed to get a big battery to go under the bow....which has a quite wide opening but only 7.5" high, he suggested THREE of his smaller batteries in parrallel. Their total weight was over 60 lbs!.The little battery I have weighs between 2 and 3 pounds. It didin't make sense to me that a digital sceen....probably LCD should use all that much juice.


And...I was, am concerned about connecting both the trolling motor and the fish finder to the same battery. BTW I would not normall purchase such a fish finder. My family had been sending me gift cards over the years to Bass Pro and I had not used them. I am not near a Bass Pro. Finally did it...and only costed me $175 with free shipping.


Thank you guys very much for the info. I feel a lot more at ease now going out and trying out the used foot controlled trolling motor I just installed and the fish finder. Thank you very much indeed.


Seriously & Sincerely,


jim