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marine batteries


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08-08-17, 04:55 AM   #1 (permalink)  
marine batteries

i have a boat that is wired for a 12 volt marine battery. I have pared down the components that i need to run from battery. all i need is power to run my fish finder and the boat running lights. I do not need electric power to start the boat motor. I would rather not have the physical weight or expense of a full size marine battery. Is there a smaller, rechargeable battery out there that can do this job for me? thanks

 
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08-08-17, 07:58 AM   #2 (permalink)  
There is no set definition for a "marine battery". So, even marine batteries are available in different sizes and voltages. First you need to calculate the load you'll put on the battery and how long you want it to power those devices. Once you know that then you can pick a battery of sufficient size. You'll still probably want a deep cycle battery even if it doesn't have the word "marine" on it. There are other smaller and lighter battery technologies that can do a comparable job but they are more expensive than old fashioned lead based batteries.

 
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08-08-17, 09:00 AM   #3 (permalink)  
questions..

i have brought this question to marinas and battery stores etc and can't get any more detailed answers. does this smaller battery have to be for 12 volt systems? can anyone give me more detailed answers?

 
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08-08-17, 09:13 AM   #4 (permalink)  
You need a 12 volt battery if you intend to run a 12 volt device off of it. Less voltage will mean it won't work correctly and more could fry it.


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08-08-17, 10:06 AM   #5 (permalink)  
You could get a 12 volts lawn mower battery.They are much smaller but will not stay charged as long.

 
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08-08-17, 10:08 AM   #6 (permalink)  
Sure whats the fish finders data plate say on it?

And how many running lights do you have? Are they LED? What type bulb?

Once we determine that you can probably use a verysmall battery. And most likely couple it with a small solar panel for runing fish finder in the day..

After we have that info and how many hours a day you will use these devices we can guide you better...


But many fish finders run in the .5 - 2 amp range. Led running lights I would say .5 amps maybe. A 10 watt anchor light will draw .2 amps.

So it you add this up for say 8 hour day that will be say on the high end 15 amps for 8 hours.

Not draining a battery below 50% you want to find a 30 AH battery. And a small solar panel will help greatly.

But portable power stations are as big as a battery... Whats your goal? Lighter weight?


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08-08-17, 10:10 AM   #7 (permalink)  
99 bucks...


https://www.walmart.com/ip/Schumache...ation/46167068



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08-08-17, 11:40 AM   #8 (permalink)  
battery

weight and economy are goals. the fish finder is an older eagle fish easy. the running lights in the boat are older, single bulb units. will the power station you noted do what i need it to do? does it have a setting or plug in that will meet my needs? it looks like a handy gadget.. thank you all for posting!

 
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08-08-17, 11:46 AM   #9 (permalink)  
fish finder and lights have no data plates or indicators.

 
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08-08-17, 03:38 PM   #10 (permalink)  
The running lights are roughly 12-15 watts each for incandescent.
That would be roughly 2.5A for both.

There are several units in that line of fish finders. The one I looked at had 1/2A in it's specs.


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08-08-17, 07:29 PM   #11 (permalink)  
On the SJ1 12v 18ah is the battery
So I am not sure how far you can run that unit I posted below. But if you use the 50-40% rule is about 11 Ah.

So if you change your incandescent bulbs to LED type you will run longer.

1. How many lights do you have?
2. Are they small marker type or like 1156 bulbs?
3. What model fish finder?


FishEasy 350C
FishEasy 350C Portable
FishEasy 245 DS
FishEasy 245 DS Portable
FishEasy
FishEasy 2
FishEasy 240
FishEasy 250 DS
FishEasy 320C
FishEasy ST


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08-09-17, 06:04 AM   #12 (permalink)  
eagle, fish easy. 3 small marker bulbs total. thanks.

 
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08-09-17, 09:30 AM   #13 (permalink)  
Well do whats best for you. Regular bulbs draw a cerain amps. If you change to led then #'s are lower.

Possibly you only have 194 wedge type marker lights..

Regular Bulb vs LED
194 bulb 0.25A vs 0.04-0.05A
1156 bulb 0.57A vs 0.07a


So 25a x 3 = .75 amps x 8 hours = 6 amps. ( Thats a lot IMO) where 3 led bulbs would use 1 amp in 8 hours.

So if you want to bring a smaller compact type battery you need to change to leds.

Now the fish finder.

Is this your unit?


http://www.eaglenav.com/upload/Eagle...Manuals/ez.pdf



With the lights on looks like it usues .5 amps. Thats 4 amps for 8 hours.

Total if you change to led is 5 amps in 8 hours. I use 8 hours as a fictitious #.

So that little charging station I linked to would be a good fit. How to connect it to your boat? There are probably 3/8 ring terminals on your boat?

I would hack the ring terminals off and install a anderson type trolling motor plug on the boat side. And then hack off the two battery clamp ends on the power pack I linked to and install the other end of the trolling motor plug.

Then every-time you get in the boat just plug it in.

Benefits that 18ah unit will give you huge reserve for charging phones too with its usb ports. Has a little light. etc.....

Trolling Motor Connector Kit - 8-Gauge | Bass Pro Shops

[ATTACH=CONFIG]84028[/ATTACH]

Attached Images
     

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08-09-17, 09:37 AM   #14 (permalink)  
On second thought I dont think we want to hook up that power pack to the boat that way..

Thats for jump starting batterys.


I think an adapter could be made for the 12volt cigarette lighter outlet on that unit...


Let me research...

But specs say you can draw 15 amps from that plug..

Peak Amps: 1200A
DC Power Outlet: 12V | 15A
AC Power Outlet: 120V | 1.7A
UBS Ports: 2A PER SIDE | 4A TOTAL
Air Compressor: 100 PSI



This is pricey but 12 lbs and 14 aH


http://www.goalzero.com/p/164/goal-z...-power-station




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08-09-17, 10:12 AM   #15 (permalink)  
OK lolol this is even better.

Get this battery box power unit. $50 on amazon. And put small battery inside for light weight. Then just ring terminal boat to the front 3/8 lugs.

https://newportvessels.com/newport-v...t-battery-box/

https://www.amazon.com/Newport-Vesse.../dp/B01AE2TG7G



Mike NJ




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08-10-17, 10:26 AM   #16 (permalink)  
thanks for your efforts. the fish finder link you sent looks like the same unit, the stickers are a little different. overall, simplicity and cost are my aim so i can worry about holder boxes, connectors and such. i am eyeing a simple 12 volt, sealed lead battery with 20-30 amps capability. how do i know if these are rechargeable?

 
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08-10-17, 01:04 PM   #17 (permalink)  
All lead acid battery's are rechargeable AFAIK..


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08-10-17, 09:05 PM   #18 (permalink)  
My experience with the term marine battery is that they are deep cycle/starting batteries.
They have both reasonable cranking power and reasonable reserve capacity.
You can see this if you compare the cranking amps and reserve capacity of different types of batteries.
It's the reserve capacity that reflects the battery's deep cycle quality which is what you need.

As said, the term marine really doesn't mean much.
Look for reserve capacity rating which is reported as minutes.
It's the number of minutes the battery can operate a 25 amp load to a battery level of 10 volts.

24 series lead acid deep cycle batteries from a box store that starts with the letter W are relatively inexpensive and can be charged with a regular automotive battery charger.


GregH.........HVAC/R Tech

 
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08-13-17, 08:11 AM   #19 (permalink)  
you are awesome. thanks for all the info. there was an amazon posting on this thread yesterday for a $36.00 battery. i don't see it now?

 
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