How many batteries for fairly robust Wetsounds System?

[8urchvy]

So, I am upgrading my system in my 2007 SANTE 220 TE. The boat has the dual battery option already but I am thinking with the new system, I will need an extra battery or two.

The system that is going in is WetSounds: 2 Rev10's, 6 XS-650's and one JL 12W7AE. The amps are SD2 (Sub), SD4 (Rev10's), SD6 (Cabins).

How many batteries should I run? Pictures of location and battery setup will likely be the most helpful. That way I can show my installer...when I get there.

If there is another thread on this...just send me the link and I will check it out.

Thanks !

[MLA]

How many batteries should I run? !

Just one to start the boat and make the stereo play. How may, is going to depend on how long you want to play the system with the engine off.

[David Analog]

First, I'm not entirely comfortable with an WS SD2 bridging into a 3-ohm load. Since the SD2 is rated as stable into 2-ohms stereo or 4-ohms bridged I would want to get the nod from Wetsounds on this. Generally that particular W7 woofer is best served by a strictly regulated monoblock amplifier, like the JL Audio HD1200/1 for example. I like the Wetsounds amplifiers as used in the other applications.
As for the battery size and quantity requirements there are countless variables that impact the play time. So your particular habits will be a good starting point. For instance, how loud and for how long when at rest and typically what type of music?
Here are a couple of other factors to consider....
With this type of system it is likely that the alternator cannot recharge the stereo bank after a long duration at rest. You will need a strong and smart AC shore charger to correctly service the batteries if you play the system at rest for a lengthy duration.
The size of the battery stereo bank plus the depth of discharge will determine the amperage capacity of the charger.
You do not want to routinely discharge consumer grade deep cycle batteries below 11.8 volts if they are to perform well and long term. So you need enough reserve capacity to limit the discharge.

[nyryan2001]

8- we'd be able to dial in a reccomendation from you if you were to articulate how long you'd be floating and playing music with the engine off. Example: 2-3hrs at 70% volume party cove girls dancing..... or 1hr at 30% volume in between wake sets. and then articulate how many times you'f be doing that... Sat and Sunday? and do you have a battery charger installed on your boat.

[8urchvy]

Thanks guys...I'm calling wetsounds on the sub...hope that works.

As for the time spent listening, I would say that we'll be playing the stereo at 30% most of the day with a 1-2 hour at 50%-70% in the afternoon. Probably the same routine over a two day period (sat and Sunday). I will be able to plug in the boat at night to do a recharge.

Appreciate the help!

[David Analog]

In any case you only need a single group 24 battery for starting. From there it's an estimate.
For the stereo bank I might suggest two group 31s. Upon your first test you can measure the stereo bank after a typical long duration playing the stereo at rest. If you maintain 12.0 volts or above prior to getting any type of charge then you have plenty of capacity. If not you need more and you would want to expand as soon as possible with a new and identical battery before any age accumulates on the existing bank. But again, from your description this should be plenty.
For the above battery system ideally you should have a 30 amp dual bank charger. That size may come in a 3-bank only even though you would use just two of the charger's banks.
70% of full volume, as you perceive volume, is just a small fraction of the potential power usage.
The right system set-up and tuning can make a major difference in current consumption.

[8urchvy]

Thanks David. To clarify, you recommend a dual 30 amp or dual 15 amp totaling 30? I found this dual marine 30 amp.

Dual Pro 12v 24v 30 Amp Waterproof Marine On-Board Charger DPPS2

http://www.batterystuff.com/battery-...ers/DPPS2.html

Thanks.
Rick

[David Analog]

Rick,
Dual Pro is a great, great quality charger. No question about that. However, for your specific application it might be better if you found a 30 amp 2 or 3-bank charger that is actually 'distribute on demand' rather than limited to 15 amps per each of two banks. The starting battery will rarely need more than a maintenance charge consisting of one amp or so. There will be times that combining the two banks when underway, the depleted stereo bank will siphon off the starting battery somewhat resulting in the starting battery needing a bit more of a charge. That's normal. But a deeply cycled stereo bank alone could demand over 20 amps initially. And it requires a good amount of energy to chemically excite the battery and overcome the effects of sulphation (not important in maintenance only scenarios). 'Distribute on demand' means that the charger can deliver the bulk of its collective capacity to the bank most in need.
Just to mention a few but not limited to, you can find quality dedicated marine chargers from Intelli-Power, Xantrex, Dual Pro, ProMariner (in both ProTech and ProSport series), Ctek, and Guest. Ctek will perform stronger than the current capacity would imply because they are using pulse technology. Guest may not feature D.O.D.

[nyryan2001]

8- I'd rec your dedicated starting battery on one bank and 3 deep cycles on the other. 70% volume for 2 hrs is substantial.

Also, I disagree with David's charger rec. chargers are spec'd per bank to charge and condition roughly 1 battery per bank. If you go with 2-4 batteries in your stereo bank a two bank charger as he rec'd would be weak and under spec'd. It'd definitly charge over 5 days... But maybe not on Sat Eve to have it fully ready for your trip on Sun. You definitly won't condition your batteries at 1/2 to 1/3d the spec'd amps. Conditioning is pulses that extends life by preventing desulfurization. Underspec your charger too far and you'll burn it up, not covered by warranty, I had a pro mariner go this way.

Get a 3-4 bank charger and put 2-3x those extra charger leads on your stereo bank for the number of batteries you have on there. Some manf allow it, some don't, call their tech service and ask.

FYI I am on my 6th? 3+ battery setup over the years. Currently have a true 4000w stereo, 1 Srm29 as a starter battery. 4 Srm29s on my stereo bank. 4 bank 15a x4 60amp charger, 1 bank on the starter and 3 banks combined on the stereo side.

Also, no battery manf will rec any setup where they are combined other than for all to be the same. They will rec against mix and match of wet, gel, and some even sizes and capacities.

[MLA]

Not all chargers distribute their output equally between the banks, but some do, Some, have a set output for a dedicated cranking bank and a higher output for a dedicated house bank. And some distribute on demand, and put their rated output to the bank that needs it the most. Chargers also look at the load on each bank. This is based on the total Ah's and state of charge. These chargers do not actually know how many individual batteries make up a bank. 2 group-24 wired in parallel can place the same load on a charger as a single large group-29/31 will.

Rick, Take David's advice. He's spot on based on the info you've presented. He has not given you an under sized charger rec, you just need to make sure the one you choose is an "on-demand" as stated. Two 31's in parallel could be about 200Ah, so a 30A charger would be well above the 10% rule.

[nyryan2001]

[Content removed for not following the site Terms of Use] Call Pro Mariner tech service for example and ask them if - smaller ProSport 20-30 for example is designed to put 2-3 deep cycle batteries on a single bank.... And how possible damage could follow and warranty voided.

I'd have thought the charger would have charged up to its limit and functioned fine regardless I it was 1 or 10 batteries. Not always the case. I leaned that the hard way. But don't believe me [Content removed for not following the site Terms of Use] call and ask for yourself.

[David Analog]

A couple of things to add to this discussion.
A ProSport is a great value charger but entry level. You get what you pay for. It's not the most robust quality to begin with and certainly not ProMariner's best offering. A ProSport 20 can safely service 200 A/Hs of collective battery reserves. Larger in a maintenance capacity but no larger when servicing deeply cycled batteries. If someone tries to extend the life of a battery(s) that should have already been replaced, this places extra stress on the charger. If someone tries to use it as a power supply to power a very large system while garaged it can fry. A ProSport series is a sealed design so that it can be located within some engine compartments. But that impedes its ability to dissipate heat, not as much as a fully potted charger, but still limits its duty. So don't overlearn or misdiagnose one experience.
A three bank charger wired to three paralleled batteries cannot profile and charge the three batteries independently. It can only read the bank as a whole. In contrast, a three or four bank charger can service in isolation a trolling motor bank when in series in an open circuit. A very different application. There is no advantage in this case in having a separate bank per each battery. Two banks are all that is required. Correctly matching the amperage capacity is more critical.
Too small of a charger capacity and you can't adequately reverse the effects of sulphation. Too small of a charger and you may place too much load on the charger. Too large of a charger and you can damage the batteries. A charger capacity of a 10 to 13% window of the A/Hs is a good guideline.

[David Analog]

Just to clear up one final point. Here is what ProMariner states about "Distribute-On-Demand":
"Distributed-On-Demand™ Technology
Automatically charges and maintains your engine crank battery while
distributing all remaining charging amps to trolling motor or house battery(s)."

That language is very clear. "....all remaining charging amps....battery(s)."
From a practical standpoint you could have a multiple battery bank with a short term need approaching 20 amps on a single bank of a 30 amp charger. But in the extreme, you would not want to place a potential 30 amp draw on one bank of a 20 amp charger. Kind of obvious.

[David Analog]

Oh yes, almost forgot the 70% level subject.
When most would describe their operating level they would mean that 70% relates to a portion of the maximum volume level.
The ratio of acoustic level and power level is by no means a linear ratio. If 70% level means a 10 dB reduction then that translates to 1/10th power. If 70% level means a 6 dB reduction then that translates to 1/4 power. A 3000 watt system @ an unrealistic 14.4 supply voltage at particular impedance loads might equate to a more realistic 75 to 80% of that with real world voltages at rest. So then it is easy enough to divide the wattage by the voltage to arrive at a DC current draw. However, music is AC content with a very dynamic range. So that 3000 watt (as rated) may only draw a continuous 35 to 40 DC amps at a 70% level. Easy enough to confirm with a clamp-on amp meter. 210 A/Hs might provide 6 hours of play time. Cycling the batteries at one/half discharge to extend their longevity and maximize their weekend to weekend performance would still provide 3 hours of constant play at the most conservative estimate. Again, it's never going to be more than an estimate as there are numerous other factors to account for. But, if measured upon the end of the first voyage as recommended then you still have an option to address it with more capacity as long as you act promptly. The cost of an extra battery may not be an issue. The space may be more of an issue. And you may want to test before selecting your battery charger since any change in battery capacity is likely to impact the charger selection.
So as you can see there is a lot to consider. Not something I do without thoroughly thinking it through. Something I do with all my recommendations. Don't want to be a one dimensional thinker in a three dimensional world, if you know what I mean, and I think you do.

[nyryan2001]

Put more than 2 of the smaller deep cycles, or one big 29, on a single 15a bank and you've exceeded spec for most chargers out there and threw your benefits of a smart charger/ conditioning in the garbage. Do that and you have a trickle/maintainer. Further, his gear might not even fully recharge Sat eve for Sun AM. Bad.

It's not "obvious" as that's what your uninformed rec told OP to do. My point is dont exceed ah specs per bank, it matters, and it's not obvious, MLA also said its a great idea. A budget friendly 3-4 bank charger combined In to a 2 bank setup allows him to gets the spec'd AHs he needs on the larger stereo side from a smaller charger, without burning it up, and without getting into pricey $400+ 60-80a 2 bank chargers to get within spec. Why the installers don't recognize is that on Sat Eve at 7pm when you come off the water having hit it hard all day and batteries down to 12.4.... Then it's not till 11pm that you remember to plug in your charger, then your charger has 5-6hrs in a 150deg compartment with only 15a on one bank to charge and condition 3 big deep cycles, over spec'd in a hot compartment. And this is why guys are constantly on here complaining only getting 1-2years of battery life even with a charger on them.