How to wire dual battery to charger?

[neuro242]

Searched and read a lot but still havnt found the info Im looking for. I have a dual battery setup w/ 1-2-Both swich. I have a single 12v/6amp charger/maintainer I want to use during off season shored. I just need to know where I hook up the battery charger/tender with this setup?

Or should I remove batteries for winter and keep in warm shop charging seperately and rotating every month or so?

Or should I just invest in a dual bank charger w/ this setup? (id still like to know how to connect a single though)
http://www.iboats.com/ProSport-8-Generation-2-Onboard-Battery-Charger-8amp-2Bank-ProMariner/dm/*******.391209459--**********.643103572--view_id.391384

 

[HAV2FISH]

Re: How to wire dual battery to charger?

Best bet would be to get the two bank charger. If you just use the one bank charger i would hook it to battery #2. Battery #1 is your cranking battery and it will be maintained by the boat motor. If the boat sits for a long time you might remove battery #1 and put it on a separate charger to be maintained. Battery #2 can stay in the boat on its charger. This is why i would go with a two bank charger, both batteries stay in the boat all the time. Just my 2 cents.

 

[Silvertip]

Re: How to wire dual battery to charger?

He is talking a battery tender (trickle charger) and it's an OFF SEASON situation so the engine will not be run. First, a battery tender is not large enough to maintain two batteries. You can certainly connect it to both by simply connecting the POS lead to the COM terminal on the switch. Ground can go to the ground post on either battery. For this to work you would need to set the battery switch to BOTH. The best bet is two separate battery tenders (one for each battery) and connected directly to each battery. The battery switch can therefore be set to OFF.

 

[neuro242]

Re: How to wire dual battery to charger?

I just got a dual bank charger. Good to go!

 

[seabob4]

Re: How to wire dual battery to charger?

I just got a dual bank charger. Good to go!

 

[Ryanpm6774]

Re: How to wire dual battery to charger?

OK,

I had the same question but I just want a quick and dirty explanation of why my maintainer (Genisis Mini 1 4A) won't sufficiently charge both batteries when wired as silvertip suggested? I have a switch that is left in the "Both" position. Would this not simply charge at 12v 2A each rather than the 4Amp charge?

 

[Splat]

Re: How to wire dual battery to charger?

It will but a slower rate than is generally acceptable on these forums to prevent sulfication on the plates. Batteries should be brought back up to full charge as quickly as possible for best battery health.

 

[Ryanpm6774]

Re: How to wire dual battery to charger?

I see. Would it be an issue further if one is a cranking and one is a deep cycle? both Optima blue tops.

 

[Splat]

Re: How to wire dual battery to charger?

And BTW I disagree, a 6, and even a 4 amp charger is much more than a trickle charger. I personally prefer >15amps to bring back a deeply discharged battery, but less will work just fine.

 

[Ryanpm6774]

Re: How to wire dual battery to charger?

OK, well then if I'm not going to hurt the batteries or my charger then I'll give it a shot with this one I have. It's supposed to be pretty rugged (waterproof) etc. I had a cheaper one that I got at TSC and the inside got corroded. I keep it plugged in 98% of the time and all offseason. If it's going to ruin my $450 worth of batteries though, I will get the Genius mini2 as it is made to charge two batteries at a time independantly.

Thanks for the input.

 

[UncleWillie]

Re: How to wire dual battery to charger?

OK,

I had the same question but I just want a quick and dirty explanation of why my maintainer (Genisis Mini 1 4A) won't sufficiently charge both batteries when wired as silvertip suggested? I have a switch that is left in the "Both" position. Would this not simply charge at 12v 2A each rather than the 4Amp charge?

The easiest way to confirm that it has enough capacity is to hook it up with the Batt switch set to BOTH.
Place a meter on either battery.
Assuming a Smart Maintainer, you should expect to see the bank voltage quickly rise to over 14v and then slowly settle out to the lower 13s. The cycle should repeat every minute or so.
This assumes the batteries are already fully charged. Otherwise wait 6-10 hours and check it again.

 

[agallant80]

Re: How to wire dual battery to charger?

Option 1. Get a one bank charger connect it to bank 1 and put the switch in to ALL to charge both banks that way your starting battery is always charged

Option 2. Get a two bank charger and hook one lead each up to each bank.

 

[Ryanpm6774]

Re: How to wire dual battery to charger?

Good Answers. I think I will try hooking it the way I had it (possitive to the common terminal on the switch and negative to one ground terminal on bank 1) and use my multimeter to see what I'm getting for each battery. Then if this is not sufficient, I'll switch it to bank 1 only and keep the switch on both and see how well that trickles over to battery 2 (deep cycle). From there, if I still am not getting enough I will bite the bullet and get the Gen2. I just wanted to make sure that since bank1 is a starter and bank2 is my deep cycle that I'm not hurting either battery.
Thanks for the input. I'm going to get working on this now.