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Jason99T/A
05-11-2010, 07:58 PM
I just purchased a '03 X-2 with 3 batteries - one starting battery and two "stereo" batteries wired in parallel. Boat does have a Perko switch. My question is do I need a two bank or three bank battery tender, as the stereo batteries really are wired a single, large capacity battery?

I plan to use the following:
Deltran 2-bank Battery Tender (http://www.summitracing.com/parts/DTN-0220165DLWH/)

Thanks,
Jason

brettmess24
05-11-2010, 10:54 PM
You may be able to use your Perko switch and connect all the batteries together and then you might be able to get away with a single bank.

Emphasis on may be and might be able.....:D

I recently purchased a dual bank charger (pro mariner 8amp) and once I connected my Blue Seas ACR the Isolator connects the batteries together when charging and I would then only need a single bank charger.

So your perko switch might be able to combine the three batteries if the switch has an "ALL"

jvbaca
05-12-2010, 12:35 AM
You may be able to use your Perko switch and connect all the batteries together and then you might be able to get away with a single bank.

Emphasis on may be and might be able.....:D

I recently purchased a dual bank charger (pro mariner 8amp) and once I connected my Blue Seas ACR the Isolator connects the batteries together when charging and I would then only need a single bank charger.

So your perko switch might be able to combine the three batteries if the switch has an "ALL"

And then where do you connect the leads from your charger?:confused:

brettmess24
05-12-2010, 08:58 AM
And then where do you connect the leads from your charger?:confused:

To the "start" battery but if you have a dual bank charger it wouldnt matter. Also if you have a Blue Seas ACR it doesn't matter as it will combine the batteries when charging.

TX.X-30 fan
05-12-2010, 09:01 AM
I am on the 3rd year charging 3 with one little tender..................... They act as one battery.

EarmarkMarine
05-12-2010, 02:14 PM
Jason,

You only need a two-bank charger since the two stereo batteries are being charged and discharged as one. A three-bank charger would only run isolated profiles and charging programs if the two batteries were separated by a second switch.

'Tenders' are good for starting batteries in seldomly driven third cars, motorcycles, tractors, Jetskis, ATV & UTVs, etc, that are stored in a charged status and need to be maintained in order to offset the 3 to 4 percent monthly self discharge.

However, true deep-cycle wet batteries need a charger with current capacity that is equal to 10 to 15 percent of the batteries' collective amp/hour ratings. This will chemically excite the batteries so that they properly desulphate. Its not just about restoration time, rather its about conditioning. The right charger will extend your play time and stretch your battery lifespan.

Don't get me wrong. A tender is far better than no charger at all. But with a tender your deep cycle batteries will slowly degenerate from sulpher deposits that will bond (and eventually permanently) to the lead plates.

If you have three Group 24 batteries for example, with 165 collective amp hours, you would want a 20 amp dual-bank, three-stage smart AC charger that can distribute its total capacity on demand to the bank with the lowest charge.

David
Earmark Marine

Jason99T/A
05-12-2010, 02:34 PM
Thanks David. I believe I have a Group 24 starting battery and two Group 31 stereo batteries. Can you recommend a charger/tender (2-bank)?

TX.X-30 fan
05-12-2010, 04:07 PM
Mine still works fine and I have 3x the amp hours you state.

EarmarkMarine
05-12-2010, 05:37 PM
Jason,

Estimating that you have a 55 amp/hour wet Group 24 and two 79 amp/hour wet Group 31s, for a total of 213 amp hours, the smallest charger would be a ProSport 20 2-bank charger. Its a little light and doesn't provide much latitude in upgrading batteries.

The best option would be the Intelli-Power PD2130V 30 amp 3-bank. This would give you the capacity to upgrade to AGMs where two Group 31s and one Group 24 could represent 300 collective amp/hours. This would safely connect with one bank to each battery although the two paralleled batteries would still measure and charge as one unit.

From another perspective, dual Group 31s provide greater reserves which usually translates to shallower cycles and therefore longer battery lifespan. On the other hand if these are deeply cycled the two 31s present a serious load on the alternator. There are scenarios like a long play time at rest, a short run back to the trailer or slip with much of that time spent at idle through no wake zone or waiting in-line and with the stereo playing continuously. You'll get nothing but a short term surface charge under these conditions. This may also cause an ACR/VSR to bounce open and stay open providing little restoration from the alternator. Larger batteries and larger stereos increase your dependency on shore AC charging.

I don't believe in a single prescription that fits all systems. In order to strike a balance between convenience battery' longevity and alternator preservation, the scheme should change as your audio system grows. Sorry for the ramble but its a really involved subject.

David
Earmark Marine

Jason99T/A
05-12-2010, 07:35 PM
David, thanks. I have three Optima Blue Tops in the boat now.