Operating dual battery

[GoingFishing]

Gday Raiders

The internet is a very big big place isnt it. You would think that with the amount of information available finding answers should be easy. These days i find too many answers, most of which contradict each other !

Anyway, looking for realtime responses from those who operate dual battery packs. When your out for the day fishing do you only use one battery or both ?

I dont run alot of electronics on board, just lowrance gps/sonar, evinrude touch screen and hardwired radio. Occasionally the pump for live bait well and deck wash will come on.

Would i be best off using one battery when out and about, and alternate between battery 1 and battery 2 on each trip? 

[PaddyT]

Ok I run 2 Lowrance head units , a radio , live bait pump , 2 bilges etc . Battery one used on the way out , battery 2 is used on the way home - so half the day on one, half on the other

[rickmarlin62]

we usually run on both while travelling.then turn back to one while sitting..that way if that battery loses too much power to turn motor  turn on second battery and your right to go..rick

[antonywardle]

two batteries, one starter, one toys. I have a VSR between the two of them and only charge the starter when running with any excess going in to the second battery. I put them both on charger before I go out.

 

cheers

 

[Ducky]

I’m no electrician by any means but why do you need a 2nd battery at all assuming it is 12v and you’re not running 2 x 6v in series? Is it for the leccy or just back up for piece of mind? When my project is finished I’ll have my trolling battery hooked up to a volt sensitive relay so when the alternator has the starting battery charged (starting battery runs the accessories too) it will automatically switch over to charge the trolling battery.  Good for those long weekends using the leccy when access to 240v (battery charger) is limited or non existent. I imagine your starting battery has the appropriate crank for the outboard. 

[zmk1962]

Hi Sam,

I run with both batteries on since installing the Anchor Winch (but in hindsight perhaps I should have been running that way all the time because of the specific characteristics of the motor that I have). I have no VSR.  There are several other considerations than just power drain/consumption requirements in deciding how you want to run. There are also different types of VSRs out there now, and depending which type you have and how your boat is wired can also be a consideration. 

I'm happy to draw and talk through a few circuit diagrams and their pros and cons with we meet up next week.

If you have time, rather then point you at the whole www have a read of the discussion on this recently in response to Bear's question here: 

If its urgent... give me a call tonight.

Cheers

Zoran

Edited January 16, 2018 by zmk1962

[back cruncher]

Hi all...I use both batteries on day trips.overnighters I use one battery so I got a full backup if needed.

im curious why boats don't use the same systems as 4x4  ???

[GoingFishing]

Certainly seems like a far more complex question than I anticipated! 

At the time i purchased my boat the dealer told me i can operate the boat on a single battery so hence my question. I currently run on both batteries

One thing that i didnt mention (and assume has some impact on the end answer) is that my ETEC G2 150 HO produces 133 amps, 50amps of which are purely dedicated to battery charge and operations of equipment whilst the motor is running. 

With 50amp spare coming off the motor and with only two touch screens running id be surprised if i ever ran out of battery running a single battery? But when it comes to electrical engineering i am absolutely illiterate so i could be 100% wrong 

Zoran thx for the offer and will do a bit of homework on how everything is currently wired up on my boat before i come over for a beer so that all my answers arent "not sure il have to check and get back to u" haha ?‍♂️

Edited January 16, 2018 by GoingFishing

[GoingFishing]

PS - i dont have a VSR

[Guest Guest123456789]

I’m also no electrician but based purely on how good 7 stage chargers work I charge/use both batteries all the time. My main worry for charging just one battery using the outboard would be damaging the battery by giving it too much power when it’s almost full. Also I’m too busy doing other stuff to play around with battery toggles and they’re always fully charged before setting off anyway. Might hange it if we have an electrical engineer amongst us who knows a better way.

[zmk1962]

1 hour ago, GoingFishing said:

Certainly seems like a far more complex question than I anticipated! 

At the time i purchased my boat the dealer told me i can operate the boat on a single battery so hence my question. I currently run on both batteries

One thing that i didnt mention (and assume has some impact on the end answer) is that my ETEC G2 150 HO produces 133 amps, 50amps of which are purely dedicated to battery charge and operations of equipment whilst the motor is running. 

With 50amp spare coming off the motor and with only two touch screens running id be surprised if i ever ran out of battery running a single battery? But when it comes to electrical engineering i am absolutely illiterate so i could be 100% wrong 

Zoran thx for the offer and will do a bit of homework on how everything is currently wired up on my boat before i come over for a beer so that all my answers arent "not sure il have to check and get back to u" haha ?‍♂️

 

43 minutes ago, GoingFishing said:

PS - i dont have a VSR

Sure. No probs.  Once we chat it will probably generate a bunch of questions and you'll probs be talking to Evinrude anyway - I know I rang Mercury to validate some things about how my motor would behave under certain battery conditions. That article you snapped mentions 50AMPs dedicated to charging the "house" battery. That's usually a term reserved for dual battery set ups, where one battery is a starter and the other the house battery. So the implication seemed to be that e-tecs run with 2 ...But I did a quick google and it showed a typical e-tec G2 installation wiring with just one battery...  so I think you have 50AMPs charge output for battery(s) in total and the other 73AMPs go to driving the electronics on the motor itself.  

But if the manuals that came with the motor also show a wiring diagram it would be good if you could snap and send that to me - or bring it along. 

Generally with such hi AMP out motors the G2 (or even my 1999 Merc which puts out 40AMP) you don't have a problem with a battery running flat when the motor is working or has worked for a while and recharged the battery(s)...and the few low AMP devices you are running are unlikely to drain your battery.  The consideration really come down to being clear about what scenarios you want to protect your self from and your style of fishing. 

Cheers

Zoran