Auxiliary Battery Charging

[Haji-Baba]

I have an Auxiliary battery in my larger boat which powers my sounder and gps.

If I ran a pair of cables from the main starter battery to my auxiliary will this charge the second battery

I don't need this arrangement hooked up permanently but lately I have been going down to Bribie for a day's fishing and having not used the boat for some time before hand need to put the second battery on the 240 v. charger.

The motor is a 60 Hp. 4 stroke Yamaha. I have a voltage readout on the sounder and gps to indicate full charge.

Any info would be appreciated.

Have fun Haji-Baba

[tjotter]

is the Aux battery a deep cycle ?

nb: I put a 240v charger on the deep cycle Aux the day before, and the day after, any trip as it is the simplest option.

[PixieAU]

I would have thought the first thing they would do is equalise between them. So you would be draining the starter battery until the second battery charges up to equal the first.

I'm no expert so this may be wrong.

[Chimo]

Haji-Baba

I have the same setup in my Vagabond and I got one of the locally made auto battery couplers fitted.

It links the start battery to the house battery so the start battery charge flows to the deep cycle house battery and this happens when the motor is running. When your motor is not running the house feeds all the non-motor electrics.
If you reduce the house voltage below a certain voltage the motor battery disconnects from the house so that you can safely start the motor.

Also when you turn the key to start the motor and the motor voltage drops the house disconnects so when the motor starts the electrics dont get any screen destroying spikes. You don't have to do anything its all automatic.

When I charge the motor battery at home I connect, via a timer for a an hour or so; the charger (Ctek M300 14.3v or another 5 or 6 amp chargers13.5v) on to the motor battery and the ABC connects the two or three if I link the second house to the first house battery.

I was recently trying to remember the age of the batteries and its crazy but it seems like its going on for 8 or 9 years. I just gave the motors a run and they started first turn of the keys but they are old-tec Evinrudes!

Cheers
Chimo

[FNQCairns]

I have an Auxiliary battery in my larger boat which powers my sounder and gps.

If I ran a pair of cables from the main starter battery to my auxiliary will this charge the second battery

I don't need this arrangement hooked up permanently but lately I have been going down to Bribie for a day's fishing and having not used the boat for some time before hand need to put the second battery on the 240 v. charger.

The motor is a 60 Hp. 4 stroke Yamaha. I have a voltage readout on the sounder and gps to indicate full charge.

Any info would be appreciated.

Have fun Haji-Baba



You dont actually need that battery charged in real time (if the load stated is your total load daily) so long as it's not like a vesper motorbike battery.

Outside of a surface charge so unless one runs 40km continuously (so an hour?) to their next fishing spot the charge repair of a house battery is pretty weak to next to useless.


My house (it is bigger than the starting battery and hides under the CC) is not connected to the main engine charge circuit.....if 48 hours of continuous house battery use happens (including led overnight lights) I will carry an extra battery for that trip.

Daytrips with competent sized battery's present no expected problems and even if the start battery dies on end of day start up the house when swapped out will get one home.....just ensure trhat at every instance decent sized/capacity battery's are the only ones that ever see a spot on the boat.

pay that extra IMO.

[Haji-Baba]

Thanks for the advice members, my house battery does not do a lot of work only the sounder and gps most days. Occasionally an evening fish and runs a few lights.

The problem is that lately I have been going down to Bribie from Brisbane for a day fish and as a result have not been able to put the charger on the night or day before .
which has been the norm before this.

Hasn't been a problem yet but I like to keep it fully charged mainly to be used if the starter one fails.

I do have charging systems in my ute for van and tinnie batteries but nothing on the bigger boat.

I will figure it out eventually.

The obvious solution would be to bring the battery home and put it on the charger here.

As you get a bit older you look for the easy ways to do things.

Thanks again.

Have fun Haji-Baba

[ranmar850]

Chimo has it there. There are purpose-built marine battery switch/ smart relay combos available. I had one on my last boat--Three switches--House, Crank, and Both, and a smart relay intergrated. Leave Both switch turned off, and you are starting on Crank, running your accessories on House. Accessory battery connected to House will charge when the smart relay monitoring Crank sees more than 12.2(?) volts. When the start battery connected to Crank drops below this voltage, smart relay disconnects ,(think Redarc on a dual battery 4wd, same thing) so your accessories cannot drain your staring battery, which is connected vis Crank. If you need both to start, turn Both switch to On position, and the two batteries are parallelled. Foolproof, compact(approx 210mm square) and not expensive ($200-ish?)

[Chimo]

Ranmar850

The ABC referred to in post 4 does all that you mentioned however it automatic so you don't need to do any switching which really suits me. Also any newby on the boat does not have to learn about what to touch and what not to and that is a lot safer too.

Cheers
Chimo

http://www.ausfish.com.au/vforum/attachment.php?attachmentid=109820&stc=1http://www.ausfish.com.au/vforum/attachment.php?attachmentid=109821&stc=1

[ranmar850]

Looking at the circuit--so it always starts on main battery, then connects house battery into charging circuit ala' smart relay /redarc I mentioned--does it allow you to parallel both if the starting battery is a bit sluggish, or do you only have one option for starting? Any manual override? House battery solenoid has 180 amp rating, good--I can see the attraction of a fully automated system, but are you now totally reliant on the electronics of the ABC for a start? Not that I am afraid of electronics, as I am an electrician by trade--as long as the leads are long enough to bridge the black box out and go direct I guess you are safe enough.

[Chimo]

Ranmar 850

You do appreciate the finer points and did ask the critical question. Thanks for your professional assessment. The guy who sells and fitted mine is a local Gold Coast electrical engineer who worked with the other similarly qualified gentleman who I believe conceived and first built the units.

The Vagabond has two motors and each can be isolated from their battery by a simple, inexpensive, plug in "key" switch. ( I am sure you know the type.)

As well as this I have a third key switch that links the two start batteries.

In the years that I have owned the boat I have only had one start battery play up and by linking the start batteries I was able to start the motor with the failed battery then unhook the connection between the motor batteries, then start the "good" battery motor and motor on as usual.

Regarding your other concern about the ABC failing, I guess in that unlikely event I would link the motor batteries, start the motor whose battery was connected to the ABC then disconnect the link and start the other motor so I believe I would still be able to operate as per normal.

Cheers
Chimo

[the gecko]

Linking batteries by proper switches and or Voltage Sensitive Relays VSRs as mentioned above is great, I use a VSR myself. But until you get your setup professionally rewired, I would NOT link the batteries when charging.

All you need is a $10 multimeter.

You main cranking battery shoud read 12.8v or better, and should never need charging. It should be charged by the engine when its running. So unless it has been off the water fo so long that the charge has dropped below 12.6v, you dont need to charge it. Just check it with the multimeter.

Your accessories battery should be charged if the reading falls below 12.8 v. Charge it seperately, until you have the time and money to install the suggested wiring and switch systems. It will take 6-8 hrs to charge, depending on the charger strength. Mine only runs a sounder, gps and led lights same as yours, and I can get 5-6 trips out of each charge if I need, although it helps to charge it more often than this.

Accesory batteries must be deep cycle, and are best charged after each trip, not the day before a trip. This will greatly extend the life of it.

[TheGurn]

So what's the general attitude on the 'float chargers' (battery minders I think they're sold as) that can be left on all the time to trickle charge when required. Apart from having to check the fluid levels regularly, I thought these were a godsend for batteries that sit for long times between uses. Have one hooked up to my 4x4 to stop the electronic rust doohicky thing from flattening the battery every week. Works a treat.

Cheers
Reg

Sent from my HTC Wildfire using Tapatalk 2

[ranmar850]

Chimo--sounds like a good system when you can extend it to twins as you did. Does some peoples' heads in trying to manage twins properly:)

[ranmar850]

I'm a believer in the Ctek smart chargers, they will most certainly extend battery life and keep them ready to go when required. Use one on a couple of motorbikes that don't get the use they deserve.