Need to maintain batteries at anchor

Maverick

Almost A Member
May 30, 2003
212
101
63
Lake Forest
Name
Bart Hyter
Boat
25' Skipjack
My boat has two batteries for running the electronics and of course starting the engine. When I do an overnight trip I must turn the batteries to one and by daylight the battery is dead as I am running the bait pump and my anchor lights. What is the best way to maintain my battery in this situation? Should I purchase a battery charger and portable generator? How do I hook it up? Add additional batteries and run a relay to them so they get charged when running the boat?

Thanks
 
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Fishbones

Your wife thinks about ME
Nov 7, 2005
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Chula Vista
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Rich
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One Off 28' Custom Built Skipjack (SOUTHWESTERN) & 18' Sylvan (Short Runs)
Dual house batteries with a battery isolator
 
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bman440440

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Sep 8, 2010
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San Diego 92117
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B-MAN
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Heisenberg(20' Maxum), Sip N' Slide (33' 2 deck w/slide) Ships & Giggles (32' double deck pontoon)
My boat has two batteries for running the electronics and of course starting the engine. When I do an overnight trip I must turn the batteries to one and by daylight the battery is dead as I am running the bait pump and my anchor lights. What is the best way to maintain my battery in this situation? Should I purchase a battery charger and portable generator? How do I hook it up? Add additional batteries and run a relay to them so they get charged when running the boat?

Thanks

what kind of bait pump are you using? I can run my bait pump(rule 750 GPH), stereo(not at hi volume), nav/anchor lights, underwater LED lights, courtesy lights and GPS/FF all night(from 8 PM to 6 AM) and my battery is not "dead" its at 11.7 volts not dead by any means... I run a dual purpose group 31 for my engine battery and a AGM group 31 for my "house" battery with an ACR that keeps the house battery charged wile the engine is running... a good quality AGM group 31 should be able to keep you going threw the night... now if you have a power hungry bait pump that might be a different story... but one thing I suggest you do is change out all your lighting to LED... that's what I did and it helped MUCHO!! also if your pump is power hungry pump is go with (2) 6 volt AGM battery's to give you more reserve power
 
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tanner.s

Fish Slaughterer
Oct 18, 2012
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Tanner
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1997 Proline 23 W/A
As above, 6V is key. Run your pump at slower speed for twice the time.

Sent from my SM-G925V using Tapatalk
 
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bman440440

I am the one who knocks!!!
Sep 8, 2010
2,817
1,263
San Diego 92117
Name
B-MAN
Boat
Heisenberg(20' Maxum), Sip N' Slide (33' 2 deck w/slide) Ships & Giggles (32' double deck pontoon)
As above, 6V is key. Run your pump at slower speed for twice the time.

Sent from my SM-G925V using Tapatalk
no... that is not why the 6v are suggested... (2) 6v in series is 12v... the 6v's generally have more capacity than a 12v single battery... running a 12v bait pump at 6v will have 2 problems... 1st more than likely you will not have sufficient water flow to keep your bait alive and 2nd it will shorten the life of your pump
 
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tanner.s

Fish Slaughterer
Oct 18, 2012
1,896
599
San Diego
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Tanner
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1997 Proline 23 W/A
no... that is not why the 6v are suggested... (2) 6v in series is 12v... the 6v's generally have more capacity than a 12v single battery... running a 12v bait pump at 6v will have 2 problems... 1st more than likely you will not have sufficient water flow to keep your bait alive and 2nd it will shorten the life of your pump
I was adding to what was said. Along with the greater capacity, you can run them in in parallel for high-draw pumps when the bait is at rest and consuming less oxygen. It works for me and the pump is over 3 years old without a hiccup. During the day, when the bait is stressed and swimming hard, we run it full speed. At night or at anchor for long periods of time, running it half power works for us.
 
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mischief1

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Jun 30, 2008
344
108
Canyon Country CA
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Dennis
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24 Skipjack "Catchit"
You may have a short that is draining your batteries. To check turn off all your electrical equipment. Disconnect your positive battery connection from your battery post. using a amp / volt meter touch one lead to the battery post and the other to the battery cable. If you have a short you will see the amperage draw not good.
I use two 12 volt deep cycle batteries from Costco wired in parallel for the house and one 12 AGM for starting. I have a selector switch so I can either run on the house #1 or the AGM #2. I all wise leave the switch on #1 and only use the AGM #2 in case of an emergency.
 
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Maverick

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May 30, 2003
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Lake Forest
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Bart Hyter
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25' Skipjack
I like the idea of adding a third battery and stringing it together with my "house" battery. If I run the battery on say number 1, will the second battery still get charged when running the boat from the alternator?
 
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dcarlisle

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Jun 25, 2008
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The Island
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Dave
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Boatless
Do the correct thing and do the math.
Figure out your amperage load. Total at night, how many hours you want it to last, have a battery bank that can handle that load and only drain down to 50% (preferably).
As stated above, make sure your wiring is squared away with no shorts or high resistant connections as that will help drain batteries quicker.
If your pump and lights equals 10 amps, and you want to run 12 hours on the batteries, to drain it only 50% from a fully charged state, you would need a battery bank capable of 240amp hours.
This is also affected by the condition of your batteries and type. Some types can tolerate a near complete discharge and others it is safer to not go below 50% or you start to loose capacity and the ability to recharge properly.
Although it is expensive, a qualified electrician will be able to set you up right the first time without you having to guess if you got it right. They may spot problems along the way that you can address and improve the performance of your setup.
 
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Derby

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Sep 9, 2010
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SouthBay SF
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The Kid
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Aquasport 222 FFV
There areally a lot of different chargers.

I use Morningstar Sunsaver Duo on the boat and a single bank Morningstar for car camping.

The duo is nice. You can select either 50/50 or 90/10 power to house and starting banks. I use the 90/10. Basically it's always maintaining isolated starting bank and giving most power too house.
 
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Derby

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Do you uave this one derby?
Amazon product

Yup. The remote display is nice too. Gives voltage, amp/hrs and direct amps to each battery as well as same stats from solar array.

But the remote is not needed if you want to save a few bucks. You'll also need TC4 solar connectors for the panel connection.

Always better to have more small panels then one big one on a moving installation. This will minimize affects of shading.
 
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hardrider5

Master
Sep 4, 2003
782
114
Huntington Beach
Name
Mike
Boat
Parker 2520
My boat has two batteries for running the electronics and of course starting the engine. When I do an overnight trip I must turn the batteries to one and by daylight the battery is dead as I am running the bait pump and my anchor lights. What is the best way to maintain my battery in this situation? Should I purchase a battery charger and portable generator? How do I hook it up? Add additional batteries and run a relay to them so they get charged when running the boat?

Thanks

Our setup is 2 group 27 Batteries in the stern and a 4D house battery. The bait pump, Nav lights will run all night long on a single group 27 battery. When we stay over night we switch the battery selector from "all" to One. The house battery has its own selector connecting too the Group 27 batteries in the stern to charge while running and then "Off" at night isolating the 4D from the other two batteries.If needed the next morning just switch over to the other group 27 to start the engines. Once started the selector in the stern is turned to all and the house battery to on so all batteries get charged while running.
If your killing one battery then I would check it. Maybe the battery is too small and not deep cycle like a Group 24 instead of a group 27. As the battery ages it will loose reserve capacity. Im changing then out every 4 to 5 years. The other possibility is your simply drawing too much current and the other fixes listed in prior posts may need to be done. We are not running LEDs yet and we are using a large Rule bait pump without a problem.
 
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GregorXr

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Oct 5, 2012
798
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Temecula
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Robin Boyer
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Patients Boat!
Are you running any solar chargers? Does one need a solar charger or just three batteries like you. I would like to have power all night and be able to start up in the morning. Only have 1 battery on my boat so far.
 
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mischief1

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Jun 30, 2008
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Canyon Country CA
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Dennis
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24 Skipjack "Catchit"
I like the idea of adding a third battery and stringing it together with my "house" battery. If I run the battery on say number 1, will the second battery still get charged when running the boat from the alternator?

The second battery will not get charged unless you install a combiner into the system, check West Marine web site for wiring ideas tutorials. NEVER switch the batteries with the motor running it will damage the alternator. Check your charging voltage at the battery post with the motor running you should be getting 14 volts. I all wise charge my batteries the night before I go out over night. Make sure they are toped up.
 
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kindafishy

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Jul 21, 2010
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hemet/ca/riverside
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SCOTT
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bayliner cierra express 2452 "RYLEE'S WAVE RYDER"
The second battery will not get charged unless you install a combiner into the system, check West Marine web site for wiring ideas tutorials. NEVER switch the batteries with the motor running it will damage the alternator. Check your charging voltage at the battery post with the motor running you should be getting 14 volts. I all wise charge my batteries the night before I go out over night. Make sure they are toped up.

i think this may be "safe" advice, bujt i dont think its true. its my understanding that modern battery switches have a "make before break" feature that "makes" the connection to next battery before "breaking" connection to the other. as long as you dont go to the "off" position while running your ok.
and if you have one with A.F.D. (alternator field disconnect) it will prevent damage to alt. if switched to "off" while engine is running.
 
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hardrider5

Master
Sep 4, 2003
782
114
Huntington Beach
Name
Mike
Boat
Parker 2520
The second battery will not get charged unless you install a combiner into the system, check West Marine web site for wiring ideas tutorials. NEVER switch the batteries with the motor running it will damage the alternator. Check your charging voltage at the battery post with the motor running you should be getting 14 volts. I all wise charge my batteries the night before I go out over night. Make sure they are toped up.

We are using individual switches for each battery so as long as we are simply adding a battery to the circuit by turning it too the on position I don't believe there will be damage to the alternator and we've never experienced any. There maybe a system out there or a switch that could be harmed but Im not aware of any.
 
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