How do I shore charge a two battery parallel system

[Mark_VTfisherman]

Re: How do I shore charge a two battery parallel system

FWIW, if you have a trolling motor, I've forund it's convienient to modify a charger to replace the clips on a charger with a trolling motor plug...

Wished I'd thought of that. Must be too simple for an overthinker!

 

[Wee Hooker]

Re: How do I shore charge a two battery parallel system

Mark, You can accomplish the same without modifying a charger. Just mount a TM plug to a 6" x 1x3 board (or anything non matalic/conductive) via ring terminals ( on the plug wires) and some brass bolts through the board. Then you just clip your charger to the bolts and the plug into the boat. Not quite as slick but accomplish's the same thing. I used this rig for years.


FWIW, I'm an engineer who has learned to "underthink" whenever possable

 

[waterinthefuel]

Re: How do I shore charge a two battery parallel system

Agreed that a land charger will work OK on land, but I still put emphasis on the true marine charger, unless the supposed "digital" charger is a true 3-stage.

DC is not a digital environment (except for ON and OFF), so that label may just be advertising hype.

Yes, it is true 3 stage, this is the one I have. Absurdly overpriced marine chargers aren't the only chargers on the planet that have 3 stage charging technology.

The digital part is that it tells you digitally how many amps it's giving the battery. It's not a needle, it's a digital display. I can promise this is as good as any marine charger you will ever buy. When I was first introduced it was an 80 dollar charger, now I believe its down to 60 or so.

Just keep it protected from moisture.

http://www.blackanddecker.com/ProductGuide/Product-Details.aspx?ProductID=15578

 

[Wee Hooker]

Re: How do I shore charge a two battery parallel system

Although I'm senseing we are getting way off topic here, I'll throw in that I use a B&D charger nearly identical to the one listed above. Two of them actually. One is rigged for /dedicated to the boat (as described above) for home charging on the trailer , the other stays in the house and charges 2-3 33Ah gel cell batteries every day for my son's wheelchair and life support equipment. ( Note that's over 10 yrs run time/day on average.) Great little chargers. Mine ( the 10/6/2amp version) auto adjust the current output based on how much the battery needs. I won't argue that it's the charger to use in a wet/marine environment but it's indestructable and of the highest quality for my purposes. ( BTW, we get an excess of 1000 charges / 4 years on one of those 33 ah medical deep cycle bateries with this charger.)

 

[pvanv]

Re: How do I shore charge a two battery parallel system

That BD unit sounds/looks like a great value.

As long as it's on land, I stand corrected. The reason that I am so emphatic about using a good charger is that I had a really bad experience with a cheap automotive bulk-only charger that literally corroded through the LU on an outboard a few years ago.

Maybe the charger thread should be an FAQ...

 

[jprice]

Re: How do I shore charge a two battery parallel system

I have a 96 seadoo speedster with 2 batteries connected in parallel. I've read through this thread (and others), but I'm still not sure of the best way to do this.

What would you guys recommend for a trickle/maintenance charge over the winter? (boat is stored in garage)
Can I just hook it up to the batteries while in the boat, or should I remove them?
If they should be removed, can I leave them wired together in parallel, or should I separate them and use 2 separate trickle chargers?

 

[ScarabSprint]

Re: How do I shore charge a two battery parallel system

I do the same thing boat in the garage with one battery. Just put a automotive charger 1.5amp slow charge and maintainer. I don't see any problem with that.