Battery help

I'm with TomS, I like to keep house/ starting systems separate. Still, since you asked, here is how I would wire a Stereo/Everything Else two bank setup with the Add a Battery 7650. I left out the LED and ACR toggle switch which are relatively straightforward. BTW - the battery labels are wrong, the two that say House are really Stereo, and the single Start battery is really Starting and House systems (Everything else).

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A three bank configuration with Starting/House/Stereo might be worth considering. Perhaps a second Group 27 for House systems, then separate out the two Group 31's and stereo as a stand alone system only tied in at the ground distribution block, and through another SI ACR 7610 (with a toggle switch on the negative connection). This way you have the 'standard' two bank Starting/House setup, each with it's own Group 27, and two devoted group 31 batteries to your stereo, that can be tied into the charging system at will. The combine function of the switch included with the add a battery package would only combine House and starting batteries, and not the dedicated stereo batteries. The only time you would want to use the toggle to turn on the second ACR supplying juice to the two stereo batteries is to top them off when the stereo is off, or playing at very low volume.

Hope you don't mind me helping you spend your money!
 
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Haha, I don't mind, my wife might!! I'm trying to figure out how much draw will be from house accessories, think it might not make a huge difference in having them on the stereo bank, at least then I know I can always get home. I had thought about doing another 27, if I did, I would look at doing those as both standard deep cycle batteries, the shore chargers can either be programmed or automatically recognize the battery type so it should be okay to mix, but I wonder if you have the ACR connected to the AGM's and it joins, what does that do to the normal Deep Cycle?
 
Once you remove stereo from the list, most of the house items don't draw a whole lot. The power steering is definitely a hog, but it's usually wired with the engine stuff.
 
You do not want to mix AGM with Flooded cell batteries. Might be better to go Flooded for start and house batteries, and have completely isolated AGM batteries for the stereo. You could top off the AGMs with a shore power charger, which could be single bank.
 
Thanks Jim, I kind of figured that, but I had thought about completely isolating them all together so it wouldn't matter, but who knows, friggin boat battery schematic would look like the wiring for the flux capacitor in back to the future! I DID however call Blue Seas today to ask them about the charge, isolate, charge, isolate cycle if my motor was running and the starting battery was low. I was told that it is what would happen if my amp draw was higher than my alternator output. He actually suggested not using the Add A Battery kit at all. He figured my best bet would be using an ML-ACR 7622 ( http://www.bluesea.com/products/7622/ML-ACR_Automatic_Charging_Relay_with_Manual_Control_-_12V_DC_500A ) with the same switch as the kit ( http://www.bluesea.com/products/5511e/e-Series_Dual_Circuit_Plus_Battery_Switch ) and I could also use a remote controlled switch ( http://www.bluesea.com/products/2146/SPDT_Remote_Control_Contura_Switch_-_ON-OFF-ON ) the 7622 has a manual override so if my start battery did get low I could isolate it and send all charge to it instead of automatically combining the banks. The SPDT remote switch can be mounted wherever and allows you quick and easy access to it. It will also cause the ACR to stay "open" and charge only start, or chose it to be in the closed position and put both banks in parallel, regardless of voltage. At least that is how my feeble mind understands it. It does solve the problem of the ACR constantly cycling, just not sure if it completely solves my problem. Come to think of it, I'm not even sure what my problem is anymore. This stuff is maddening! haha
 
Okay, here is the latest. It was suggested to me to not have the stereo hooked up to my alternator at all. I'm thinking they're right. What the thought is, and in their experience with a large stereo and an outboard motor, because the max output is 50A from my motor, and let's say my average draw is 50-80A, the alternator will be going at max output constantly and could cause it to fail prematurely. In their experience, it was as much as every couple months. That and a voltage relay (?) I think he said. What are your thoughts? I'd be curious if anyone with the tower stereo would be willing to see what their amp draw is at 'normal' volumes?

And if the stereo was completely separate, I could use cheaper normal batteries for a house and starting battery, and maybe squeeze another good 31 in. I also thought about running a good group 24 with both house and starting off of the one battery, I know, I don't love the idea of having all on one, just in case, although if I did have a matching 24 to my 31's, I could hook it in parallel briefly (boost) to get the motor running to charge it up.
 
At this point why not just go with a custom small diesel generator stuffed into the 3rd tube with a custom tank built in as well?
 
At this point why not just go with a custom small diesel generator stuffed into the 3rd tube with a custom tank built in as well?
And replace the bimini on that fancy tower with a proper set of solar panels!
 
Sooo the diesel in the center storage will stink us out so we won't want to be on the boat, and if a 50A alternator isn't enough to charge the batteries, something tells me the sun isn't going to either, unless I get a REALLY big bimini that has its own outriggers.

I am leaning towards the one house/start battery. If the biggest draw will be my power steering, and the only time I will be using power steering is while underway, the two should negate themselves. So maybe a Northstar group 24 starting/house, and 3 31's in parallel? I could still use the standard Bennington switch, have battery 1 be starting, 2 be the stereo bank, and only join in 1 + 2 if I needed extra juice to start the boat if something ever happened? What do you think? So would all the remote on wires still be put to the stereo bank? Oh, and where the heck do I shove 3 31's???
 
I have no idea where you'd put 3 of those monsters other than taking up BOTH stern lounge storage areas, which is an option from Bennington.
 
I was looking at dimensions, I know Gerry has 2 group 27 in the smaller section, and we know 2 31's can squeeze into the other section, so a 24 and a 31 should fit in the smaller section. I might see if I can get the factory to run a set of battery cables to the starboard lounger just in case my math isn't as good as I thought! The good thing about still using the Bennington switch is I can still just switch to off and not have to worry about accessories draining the start batt.
 
Derrick, I suggested isolation (not connecting the group 31's to the alternator or House/Start batteries) way back in post 44. Glad to hear Blue Sea Systems techs are thinking along the same lines. I was not aware of that new remote switch, I like it. Here's the one I was referring to:

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It's a Blue Sea Systems 8270 remote ACR panel. It also has the LED showing combining status. I have this panel on my bowrider, but if a dash mount was desired, the one you posted would be the way to go.

The nice thing about having the stereo batteries completely isolated is that you can devote your AGM $$$ to the stereo, and run regular less expensive flooded cell batteries for House and Starting. You can also scale the AGM batteries as needed; start with 1 group 31 now, then add another (in parallel) with your monster Amplifier, then possibly a third in parallel when you add your powered subs. Again, you would only need a single bank 'AGM friendly' shore power charger opposed to a dual or triple bank charger. The Stereo batteries when installed in parallel act as a single battery and so can be treated as a single battery by 'smart' charges. Here again you can save some $$$.

*Edit - just realized that you were looking at using the Bennington switch, and having House and Start as "Battery 1" and a bank of Batteries as "Battery 2". In this case do go AGM all around. It should work for your needs, and a single bank shore power charger for the 31's or a dual bank to also allow for topping off the House/Start battery could be used.

Last thing, if any accessories are wired directly to the battery positive and negative terminals rather than the far side of the switch, they will remain active even when the switch is off.
 
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Yes, the remote switch is a nice option, the only thing is after more thought, I wouldn't put the battery bank on the Bennington switch at all I don't think because how would that work? If I had it on battery 2 and the gps and everything was on 1, would they still work? I don't think so, unless I misunderstood how the switch works. Yes you had mentioned isolating a long time ago, but to me I was thinking with an ACR, this is just isolated completely! Haha as for the charger would it charge the batteries faster if I had a toggle type switch to take them out of parallel and put a 3 bank on? I am still a little baffled there. Some say that a 3 bank 15A charger will put all the amps to one bank if that's all that is hooked up so would that be 45A? Sorry if it is a stupid question, but you should expect that from me by now!! Haha
 
Derrick, with your original proposed use of the Bennington switch, it would be left at Battery 1, unless you had trouble starting, then you would switch to 'Both' to start the engine and immediately switch back to Battery 1. You would never run with Battery 2. In effect, this configuration isolates your House/Start Bank from your Stereo Bank, but allows for applying the Stereo bank to aid in starting the engine in an emergency.

On multi-bank chargers, if one were to setup a three bank charger with 15A per bank to three batteries tied in parallel, one would in effect be applying 45A to a single battery bank. No smart sensing of individual battery condition would occur. When tied in parallel, batteries self equalize. A single correctly sized smart charger is sufficient.
 
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Okay, I wasn't thinking about the stereo being hooked directly to the batteries so yeah that would work. Stupid moment! Haha
 
Food for thought - the Offshore versions of the SHO 250 have 80A alternators.
 
Hey Jim, you have a magic site for those? Hehe, there is no such thing as an SHO offshore model. At least not on the Yamaha site. They have an offshore model that has a 70A alternator. I wish I could switch and upgrade the alternator like the inboard. DANG! If only we had the big garage by the lake, then i might have been able to swing the inboard with a 230A!! We'd be laughing then!! Haha, oh well, there's always next year!!

So now to the charger, has anyone heard or used a pronautic 1240p?
 
Sorry, going by memory. Yes it's the offshore model and probably right 70A instead of 80A. Almost makes you want to go IO with the 120A alternator, doesn't it? :p
 
Well the boat hasn't been built yet!! :D
 
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