Dual Battery Setup Question

Bluebill

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i just purchased a 1993 Tournament 19 with a Yamaha 150 rigged with dual batteries and a single perko battery switch ( for one, two or Both). My question is, how to run the system so that the starting battery doesn't get run down in case the house battery is depleted during an outing by leaving the bait well on, or other house draw?
 

gerrys

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Being a 1993, I would suggest tracing all the wiring to see which is the house battery (electronices and livewell) and which is the starting battery (start and bilge pump). If they're mixed you should do some housekeeping. Then get an isolator and make the connections look like this:
battswitch.jpg
 

jehines3

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Caution, Isolators are not always the best solution since they do not allow a full charge. The typical isolator will lose 0.5-0.7 volts across it, thus if your shooting for a 14.2V charge, a 13.5V-13.7V may be all that the battery sees. the better alternative is to install a charging relay which when closed allows a full alterntor regulated output to the battery bank. A few people here have gone to the BEP preconfigured set-ups (including myself and NA2P) since it is an all in one pre "wired" (bused) arrangement. just my $0.02

http://www.bepmarine.com/Single-Engine% ... -1736.html

jh
 

gerrys

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Agree, either will work - most important to keep the starting battery charged.
 

Curmudgeon

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I have a T-225 with two batteries, also. I've opted for a "main" battery and "reserve" setup (both AGMs), and all electrics are wired thru the switch and powered by the battery selected, the other battery is isolated and fully charged.

With an electrical load no larger than I have, having both batteries working at the same time (one without supervision) doesn't make much sense. In six years of slow trolling for kingfish running an 1100 gph pump and all electrics I've never had to use the "reserve" battery. I'll use it on occasion, but I've never had to do so ... :wink:
 

jimmy's marine service

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gerrys said:
Being a 1993, I would suggest tracing all the wiring to see which is the house battery (electronices and livewell) and which is the starting battery (start and bilge pump). If they're mixed you should do some housekeeping. Then get an isolator and make the connections look like this:
battswitch.jpg

not sure what this wiring diagrahm is supposed to be...reading it,there's no dedicated "house" or "engine" battery...i suggest you look into this a little further...

whatever you do,don't follow this advice...
 

Bluebill

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BEP product

I like the BEP product for its simplicity...have not been able to locate it in any of my catalog searches. Where can it be found?
 

wahoo33417

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Not sure why you would want a house vs a starting battery on a two-battery, single-engine set up. That is the same set up I have. I just select a battery (never "both") and it starts the engine and runs the livewell and anything else I have going. Halfway through the day, I turn everything off and switch to the other battery. That way, both battery's get used and charged regularly.

This has worked well for me. I've gotten up to 7.5 years out of the standard battery's that came with the boat.

Rob
 

BobP

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Depending how often he starts the engine on an outing -

Without the guy buying new equipment or batteries, he's stuck - he has to start the engine on the start battery and switch to the house battery to charge it, since it may not be rated for starting. Then it wil charge while underway. This is for part of the day.
I don't advocate leaving it on "Both".

If both batteries were deep cycle and rated for starting, or so called dual purpose, he could start and run on one battery (either) half the day, and switch to the other battery for the latter part of the day's ride home so both will be charged upon return.

The lowest cost alternative may be to replace the house battery with one rated for starting too.
 

capt chris

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When you have a single engine dual battery situation w/ the selector switch, start the engine using either the 1 or 2 setting. If the batteries are too weak to start the engine alone, turn the switch to both and start the engine. Then move your selector switch from BOTH to either 1 or 2 and charge that selected battery. Use which ever battery you did not use to start the engine as your house battery for accessories like live wells, stereos, VHF radios etc while you are drifting or anchored without the engine running. That way you always have one battery fully charged to use to start the engine. You can charge the house battery back up as you run for home. Most newer battery selector switches make contact as you switch from 1 to 2 to BOTH so you don't risk blowing the diodes on your alternator. Make sure your switch does. What you never, ever want to do is turn the selector switch to OFF with the engine running. This will surely cook the diodes in the alternator and maybe the alternator itself.
 

jehines3

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I prefer the dedicated house battery as suggested. It keeps the engine start seperate and isolated and keeps all my electronics from rebooting when I jump from one spot to the next by starting another motor.
 

catch22

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jimmy's marine service said:
gerrys said:
Being a 1993, I would suggest tracing all the wiring to see which is the house battery (electronices and livewell) and which is the starting battery (start and bilge pump). If they're mixed you should do some housekeeping. Then get an isolator and make the connections look like this:
battswitch.jpg

not sure what this wiring diagrahm is supposed to be...

whatever you do,don't follow this advice...

Well, professor :wink: .... I could be wrong, but I think it's probably the most common set up that's used on thousands and thousands of small boats.
 

jimmy's marine service

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catch22 said:
jimmy's marine service said:
gerrys said:
Being a 1993, I would suggest tracing all the wiring to see which is the house battery (electronices and livewell) and which is the starting battery (start and bilge pump). If they're mixed you should do some housekeeping. Then get an isolator and make the connections look like this:
battswitch.jpg

not sure what this wiring diagrahm is supposed to be...

whatever you do,don't follow this advice...

Well, professor :wink: .... I could be wrong, but I think it's probably the most common set up that's used on thousands and thousands of small boats.


ya know what,you're really starting to piss me off...that diagrahm shows an isolator-for an alternator,did you know that ??? huh genius ??? most outboards have waht's called a stator,are you aware of this ??/ clearly not...also,that set up ilistrated,most if not everyone will use the switch in the "both" position...the switch controls the output,"output" being the switch sends power to both the engine and the 12v system,do you know that??? are you able to understand that ??? this set up,does not seperate the systems,meaning,you're running the electronics and the engine on the same battery,granted one is in reserve,however,simple fact is,a set up like this is prone to having the electronics shut down upon starting the engine,due to a low voltage situation...just because thousands and thousands of small boat are set up like this,doesn't make it the correct or the right way to do it...how would you,"you" meaning you,catch 22, set this up to charge both battteries on a yamaha outboard,without an alternator ?? share some of your infinite wisdom with us...here's a hint...if you do a search of my posts you'll find the way i like to see it ran,but you've probably searched my stuff so many times you've lost count,right ???
don't question my abilities or my knowledge,i've probably forgotten much more than you will ever know...

here's a little offer i'm gonna throw you..
i've got a 24' north coast at the shop right now,the boat's in to be wired up for a dedicated house battery,as well as rewire the mess at the helm area,you can come down and do that job,i will pay you the entire amount of the estimate,i'll pick up the parts...you do the job,to my satisfaction,and you ask absolutley no questions of me...how's that ??? here's your chance,you've been busting my balls long enough,here's your chance to put up or shut up...whatta ya say sport.... :wink: you wanna give me a hard time and question my abilities,as well as knowledge,here's your chance to show me your's...if you do it correctly,i'll gladly pay for a billboard in cape may telling how much of a genius you are,and how utterly stupid i am....c'mon,here's your chance...show me what you got...it's easy to sit behind a computer and type nasty comments,you do it alot,but think about this,sport,my name,my contact info is listed,the name of my buisness,all listed,what do you have??? a catchy screen name,you hide behind...again,why don't ya step up and show us all exactly what you've got...
 

jehines3

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Most builders do this because it is cheaper and understandable to the average joe. My BEP set-up blows the doors off my old isolator set-up and no switches to screw with all day long. I have found myself on the business end of plenty of jumper cables for boaters that forget and leave the switch in both. Most ask how they could have prevented it. The way described with a dedicated house and start is the best way IMO. No fuss, no muss....jh
 

jimmy's marine service

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jehines3 said:
Most builders do this because it is cheaper and understandable to the average joe. My BEP set-up blows the doors off my old isolator set-up and no switches to screw with all day long. I have found myself on the business end of plenty of jumper cables for boaters that forget and leave the switch in both. Most ask how they could have prevented it. The way described with a dedicated house and start is the best way IMO. No fuss, no muss....jh

the exact way described,it's real rare to see that,normally it's the switch and 2 batteries...some mfg's are beginning to use the aux charging wires on engines to power a seperate battery,however,the boat's a re still using the same selector switch,which completley defeats the purpose of a seperated battery system,if you place it in the "all" or "both" postion...
i had a customer with a wellcraft,it was a single engine rig,and the owner truly believed what the dealer explained to him,concerning the electrical system.the dealer explained for him to run the battery switch in "all",but the 12v system was powered by one battery and the engine was powered by a different battery,i removed the switch and explained the dealer was wrong,and i also explained why the dealer was wrong,the boat was corrected at my shop...his complaint was his electronics shut down when the engine was cranked...this set up shown above costs way too much for a mfg to put in from the factory,and again,it will work only on alternator equipped engines...the output wire from the alternator is disconnected and a new wire is ran to the isolator,fused of course,from the alternator output terminal...and yes there is a slight drop in voltage from the isolation diodes...personally,i prefer a blue seas acr,to the bep battery systems set ups,i use the blue seas swithes too,but that's me,there's nothing wrong with using the bep set ups...i don't like the auxilliary charging leads on the outboards,it's just me,but i don't like running a wire with all that amperage throught the tuba again and to a battery switch...believe it or not,i had a yamaha with the aux charge leads being used,the aux wire was shorted to ground,the fuse on the engine never blew-i know,hard to believe,i'm still trying to figure that one out...i showed it to the owner,an auto tech,he was astonished...if you're going to use the aux charge wires,i highly reccomend you use the ancor water proof in line fuses under the cowling,this will avoid that problem...
or,you could just ask mr catch 22,i'm confident he knows much more than anyone else concerning this... :roll: :roll:
 

BobP

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Bluebill, get more here form you post than you expected ?

You say you have a starting battery and house bank. What are the manufacturer, size (24, 27, etc.), model or at least desriptive name on both batteries, like Starting, Dual Purpose, Deep Cycle, or whateve else is written.

Where did you see the "starting" and "house" designations?
 

catch22

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All Bluebell asked was, " how to run the system so that the starting battery doesn't get run down".

Now.... a member goes to the trouble to reply with a diagram and give advice.... AND....guess what....aside from the alternator disconnect and charger.... that diagram IS the system Bluebell has!

Then.... you come along with your typical sarcastic, bashing attitude.... ("I don't know what that's supposed to be.... whatever you do, don't use that"). Just like you did to me about the prop...." bad advice"... right? You don't think that's insulting? Do you think you can say any damn thing you feel like, and never get a negative response? That's why I posted the way I did. Doesn't feel too good, does it? Imo, NO ONE ELSE insults people the way you do.

All you have to do is post your method.... period! Skip the insults, the color comentary, the opinion of how someone else "does this wrong, or does that wrong". Again, (imo)... no one else does that.

Back to the original question, as already stated... all he has to do is run on 1 battery, (all day, whatever). If you run that battery down, switch to the other, start up and switch back to charge the drained battery.
 

catch22

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jimmy's marine service said:
here's a little offer i'm gonna throw you..
i've got a 24' north coast at the shop right now,the boat's in to be wired up for a dedicated house battery,as well as rewire the mess at the helm area,you can come down and do that job,i will pay you the entire amount of the estimate,i'll pick up the parts...you do the job,to my satisfaction,and you ask absolutley no questions of me...how's that ???

Ok.... sure. What planet did you say were on? :lol:
 

jimmy's marine service

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catch22 said:
jimmy's marine service said:
here's a little offer i'm gonna throw you..
i've got a 24' north coast at the shop right now,the boat's in to be wired up for a dedicated house battery,as well as rewire the mess at the helm area,you can come down and do that job,i will pay you the entire amount of the estimate,i'll pick up the parts...you do the job,to my satisfaction,and you ask absolutley no questions of me...how's that ???

Ok.... sure. What planet did you say were on? :lol:

figured you would walk away from that offer...scared huh ??? do me a favor,grow up..
 

Bluebill

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I Have made up my mind.

It seems clear, that there are a variety of ways to operate twin batteries for one motor, but I have come to the conclusion that having a battery dedicated, and isolated from the "house" battery gives me the added safety measure that I am after, especially when it comes to protecting the sensitive electronics from the draw of the motor when it is started. I haven't decided whether to go with the BEP with the VSR or with the Blue Sea ACR system...is the lower charging rate with the ACR system really significant?

Last Question? is there an advantage to using a deep cycle for the house battery? I sometimes will be fishing for periods of several hours with the live bait tank, stereo, and possibly anchor lights on.