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phebus
01-25-2005, 02:00 PM
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O.K., here is my present setup.:
2 optima blue top deep cycle batteries
1 optima blue top starting battery
Now, this is how I use my system:
When starting batt switch is set to "all", and remains there unless I plan on the boat sitting with the stereo on (boat off) for an extended period of time. If I am going to be sitting there, I switch to the "2" position (deep cycles) so I don't run my starting battery down. I then switch back to "all" when starting the boat, and running again.
Here is my question:
Am I better off with the 2 deep cycles and 1 starting battery, or would I be better off with 3 deep cycles and doing away with the starting battery. They calll the Optima deep cycle blue tops "dual purpose" batteries, and since there are times the entire system is running of all the batteries at the same time I wonder if they should all be the same type.
Thanks

mirvin
01-25-2005, 02:14 PM
That there is a good question..... :p
I know on rv's and such they use 2 deep cycle 6 volts inline that run the coach and charge off the engine and then a 12 volt to start the motor but......???
mirvin

Music to my Ears
01-25-2005, 02:37 PM
Rick, I was checking into the same scenario and I think you're better off going with three deep cycles. And the price difference is only about 12 dollars at the site I mentioned earlier. :cool:

phebus
01-25-2005, 03:23 PM
Here is the link to the Optima site that gives the specs on the marine batteries. Optima specs (http://www.optimabatteries.com/publish/optima/americas0/en/config/product_info/marine/technical_specs.html) It really confuses me. It looks like the starting battery gives quite a few more cranking amps, but the deep cycle really doesn't have much more reserve to offer.
I need someone with some battery knowledge to interput this info and guide me in my purchase. The fact that the starting battery isn't warrantied for deep cycle use, and yet in my application it would at times be used that way makes me think the three deep cycles are the way to go.
Thanks

Havasu_Dreamin
01-25-2005, 03:27 PM
Where is HH when you need him?

phebus
01-25-2005, 03:32 PM
Where is HH when you need him?
I know, when he's moderating he's Johnny on the spot!! :D Plus, since the dreaded 6V subject didn't come up you would think he would be happy.

Tom Brown
01-25-2005, 03:39 PM
...you would think he would be happy.
I don't think that bitter son of a bitch is ever happy.
As far as batteries, it sounds like you've got exactly what you need now. Matching them closely is only necessary when they are in series.
If it's meeting your needs, I'd stick with what you have. :cool:

RiverDave
01-25-2005, 03:41 PM
Here is the link to the Optima site that gives the specs on the marine batteries. Optima specs (http://www.optimabatteries.com/publish/optima/americas0/en/config/product_info/marine/technical_specs.html) It really confuses me. It looks like the starting battery gives quite a few more cranking amps, but the deep cycle really doesn't have much more reserve to offer.
I need someone with some battery knowledge to interput this info and guide me in my purchase. The fact that the starting battery isn't warrantied for deep cycle use, and yet in my application it would at times be used that way makes me think the three deep cycles are the way to go.
Thanks
My advice on the batteries is to just go buy 3 blue tops.. Put the switch to All and leave it there. LOL.. I'm sure there's pro's and con's to that, but I've been leaving my switch to all for years with zero issues.. At the point my bass amp clips though, I can still start the boat so if I hear the stereo clip, I just shut it off and let someone else handle the sandbar DJ duties for awhile, then charge them up when I get home.
When you get your new batteries I know where you can get some cool new Optima battery boxes for pretty cheap. ;)
The latest Rev of the Optima Battery Box (Yellow/Red/Blue Top)
http://www.riverratlife.net/dave/images/CuttingEdge/OptimaPolished/UniversalD34/DSC00021.JPG
RD

phebus
01-25-2005, 03:42 PM
I don't think that bitter son of a bitch is ever happy.
As far as batteries, it sounds like you've got exactly what you need now. Matching them closely is only necessary when they are in series.
If it's meeting your needs, I'd stick with what you have. :cool:
They seem to be meeting my needs, but it is time to replace them, and wanted to make sure I was getting the most bang for the buck.

Tom Brown
01-25-2005, 03:47 PM
They seem to be meeting my needs, but it is time to replace them, and wanted to make sure I was getting the most bang for the buck.
If I was replacing them, I'd definitely stick with the non-deep cycle for a starting battery. IMO, the Optima is a great choice there.
If you're happy with the battery performance for the stereo then there's no need to switch brands. It sounds like there are some better choices though, including a single 8D format battery. You might want to search the audio forum if you haven't already read those threads.
Personally, I'm a big Optima guy. I've had amazing luck with them. That's not to say they are the best, only that I like them and I've had great experience with them. :cool:

phebus
01-25-2005, 04:10 PM
As far as batteries, it sounds like you've got exactly what you need now. Matching them closely is only necessary when they are in series.
The two deep cycles are in parrallel and go to "2" on the Perko, the starting battery goes to "1" on the Perko. When the Perko is set to "all", doesn't that effectively put all the batteries together in parrallel? If so, wouldn't it be better to match all batteries to the same type and age?

Tom Brown
01-25-2005, 04:19 PM
They're not going to have the same charge level anyway, so it would never be balanced. If you run the stereo batteries down and then select "all", you're actually going to kick the crap out of your starting battery because it's going to be charging the stereo batteries as well as starting the engine. If it were me, I'd leave it on just the starting battery until you get the engine going.
It's not a problem to do what you're doing. The battery that can most easily accept a charge... will.

Freak
01-25-2005, 05:42 PM
The ampere-hour (Ah) rating defines the capacity of a battery. A typical battery that is rated as a 100Ah battery at the 10 hour rate of discharge is capable of delivering 10A for 10 hours before the terminal voltage drops to a standard value such as 1.67 volts per cell, or 10.02 volts for a 12V battery. Similarly, a 50Ah battery would supply a 5A load for 10 hours.
The reserve capacity of a battery is defined as the number of minutes that it can support a 25 ampere load at 80°F until its terminal voltage drops to 1.75 volts per cell or 10.50 volts for a 12V battery. Thus a 12V battery that has a reserve capacity rating of 100 signifies that it can be discharged at 25 amps for 100 minutes at 80°F before its voltage drops to 10.75 volts.
The impedance of a battery is a measure of how easily it can be discharged. The lower the impedance the easier it is to discharge the battery.

bonesfab
01-25-2005, 06:48 PM
forget optimas. get real batteries. oddessy batteries or the same. BADASS!! more power smaller size. or set the big ones and have it all. they are a full drycell battery. 1200 amp, 91 reserve min., 8" x 6.5" x 7" tall 180.00; 1700 amp, 91 reserve min, 13" x 6.5" x 7" 240.00. have been using for a few years now with no headache. ;)

Mr. Naudio
01-26-2005, 05:36 PM
The two deep cycles are in parrallel and go to "2" on the Perko, the starting battery goes to "1" on the Perko. When the Perko is set to "all", doesn't that effectively put all the batteries together in parrallel? If so, wouldn't it be better to match all batteries to the same type and age?
If you are going to use the all position for any length of time (all) batteries
should be the same.
Given your current setup the all position should (only) be used if the boat wont start any other way.
Mixing batteries without isolation is a bad thing especially for a music lovin kinda guy.

LilHarley
01-26-2005, 06:07 PM
forget optimas. get real batteries. oddessy batteries or the same. BADASS!! more power smaller size. or set the big ones and have it all. they are a full drycell battery. 1200 amp, 91 reserve min., 8" x 6.5" x 7" tall 180.00; 1700 amp, 91 reserve min, 13" x 6.5" x 7" 240.00. have been using for a few years now with no headache. ;)
I have to agree on Odessy. Extremely heavy duty batteries. No gel, dry cell. Their newest one has a shelf life of 12 years. Can be charged at the full rate of your aLternator ouput. Costs some, but extremely good.
I got hooked on them for my Sea Doo's. Wow, lasted 5 years now and still going. Replacing my batteries in the Ultra with 2 Odessy's.
As far a Deep Cycle or Starting on the Optima, I believe that deep cycles have heavier plates and can take the charging for longer periods and more often. Starting batteries have thinner plates, can provide a more cold cranks quicker, but can not keep providing the amps as long as the deep cycles do. This is my limited battery knowledge ... LOL ... :supp: