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Razzman
05-08-2011, 02:13 AM
So who has one and which do you have? Why did you select the one you have?

I'm going to add one finally to the boat. After researching I see 4,5,6,10 amps per bank chargers and now i'm at a loss more or less. I've noticed most use the ProMariner ProSport 20 whether 2 or 3 bank, but do you really need 10 amps per batt to charge?

David chime in on this one if you could as well.

you da man
05-08-2011, 05:46 AM
I have 3 Deka Seamate group 31 batteries and went with a Pro Mariner Prosport 20A 2 bank charger. I don't run my stereo batteries down but better to have a good charger before you're stuck with dead batteries. David informed me that IF you run down your batteries the battery needs 10 amps to to bring it back to full charge. Plus I have an plug mounted in the V-drive locker that I can plug into from outside the boat.

lsvboombox
05-08-2011, 07:45 AM
Dual pro chargers are the best IMO.... as far as amps it really depends on how fast u need to recharge..... i use a 15 amp on my bass boat.. gives a full charge in about 4 hours... a 10 amp prob like 6-8 hrs.... if you have the time there is nothing wrong with a 5 amp... slow long charges arent bad.......

KSmith
05-08-2011, 09:19 AM
ProMariner ProSport 12 Dual Bank. Like DaMan I have a 120V inlet socket installed thru the side of the top deck in the rear locker I plug the extension cord into that powers the charger (mine is in the starboard locker as that side is closer to my garage).

newty
05-08-2011, 10:08 AM
Same as YDM but prosport12. When I plug it in its usually in for the night and by morning all the batteries are charged and ready to go.

My batteries never really get that low either because I have that 160amp alternator.

Are you keeping your same batteries or going new?

Razzman
05-08-2011, 10:34 AM
I dumped the lead acid stereo battery and added a Deka 31 AGM, got a killer deal on it. David believes I can get away with one battery based on my playtime habits.

ian ashton
05-08-2011, 12:09 PM
Do you guys play a ton without the engine running? What is the point of an onboard charger when you have an alternator recharging while your running?

bhowell
05-08-2011, 12:31 PM
Do you guys play a ton without the engine running? What is the point of an onboard charger when you have an alternator recharging while your running?

I would like to know this too. Maybe its so that playing the stereo in the garage doesnt become a problem... :D

EarmarkMarine
05-08-2011, 01:19 PM
With a battery that has a 105 amp/hour capacity you need a minimum of 10 amps of charging capacity for that battery alone. With a standard 50 to 60 amp/hour starting battery you have exceeded the capacity of a 12 amp charger. Given that your boat will usually be put into storage with a nearly charged starting battery you could use a 12 amp charger. A 20 amp dual bank charger is a better fit however. In order to have the right amount of current to chemically excite your battery in order to properly desulphate you want a charger that is rated at between 10 to 13 percent of your total amp/hour capacity.
Also, if you are maintaining a flooded starting battery make sure that you have settings that are separate for the two banks. An AGM would like to see a little higher voltage for a little longer duration at the end of the charging cycle.

David
Earmark Marine

Razzman
05-08-2011, 01:26 PM
With a battery that has a 105 amp/hour capacity you need a minimum of 10 amps of charging capacity for that battery alone. With a standard 50 to 60 amp/hour starting battery you have exceeded the capacity of a 12 amp charger. Given that your boat will usually be put into storage with a nearly charged starting battery you could use a 12 amp charger. A 20 amp dual bank charger is a better fit however. In order to have the right amount of current to chemically excite your battery in order to properly desulphate you want a charger that is rated at between 10 to 13 percent of your total amp/hour capacity.
Also, if you are maintaining a flooded starting battery make sure that you have settings that are separate for the two banks. An AGM would like to see a little higher voltage for a little longer duration at the end of the charging cycle.

David
Earmark Marine

Thanks David, exactly what i was looking for. I'll look for a good deal on a 2 bank ProMariner ProSport 20 amp unit.

Razzman
05-08-2011, 01:29 PM
Do you guys play a ton without the engine running? What is the point of an onboard charger when you have an alternator recharging while your running?

This is for more than just when on the water Ian, it's also for the maintenance factor. Also the peace of mind that if I do play over my normal the alt is not overworking trying to recharge as David explained to me on the phone.

EarmarkMarine
05-08-2011, 01:36 PM
bhowell,
An alternator is a dumb device that is intended to supply and maintain. It can't profile and condition the batteries independently. It wasn't designed to address any more than the boat electronics. That is why a fisherman doesn't depend on a stator or alternator to recharge his trolling motor bank. Its basically unheard of. And a 40 amp or more trolling motor fighting a headwind all day has alot in common with our stereo usage and nothing in common with the usage of an alternator in a car, truck or boat...as intended. Plus, alot of people are using an ACR/VSR which almost guarantees that you are putting your boat into storage with a partially depleted battery. Add to that the fact that batteries self-discharge several percent a month. If you play your system at rest and you have an audio system that draws substantial current and you have no plans of burning a tank of gas while the stereo is shut down, then an AC shore charger is a great investment that will enhance your stereo performance, increase play time at rest and extend your battery longevity. Skip over the tender/maintainer/trickle variety of chargers as they are only adequate for an occassionally driven hot rod, third airport vehicle, motorcycle, ATV/UTV, tractor, etc. where the vehicle is always put into storage with a fully charged battery.

David
Earmark Marine

rdlangston13
05-08-2011, 02:03 PM
my problem is my storage unit has no place to plug in a battery charger even if i wanted one in my boat. It is a pain in the ass to pull the batteries out and take them to the house so I just keep my Perko on "all" unless i stop and just rock tunes. Then it goes to "1" but as soon as the boat is started I swap it back to all...

cab13367
05-08-2011, 02:06 PM
I've got the ProSport20 Gen 2 which was adequate when I had two batteries totaling about 165AH. Now that I have three batteries totaling 305AH, the ProSport20 no longer meets the 10-13% rule so I have to rig up a switch that will allow me to charge just one bank at a time. Even then, 20A will not be enough to properly desulfate my two Group 29 stereo batteries which are rated 125AH each.

I am probably looking at buying two separate chargers in the future if I want to do this right.

Al

EarmarkMarine
05-09-2011, 01:15 PM
rdlangston13,
With potentially 2400 watts running at 50 percent efficiency divided by 13 volts divided by the dynamic nature of music, at full power your audio system plus boat operations can exceed the capacity of your factory alternator. When this happens the extra current demands are pulled from your batteries including the starting bank when your switch is in the 'ALL' position. When the batteries are well discharged then they become an extra load and a liability to your charging system. Once you pass a current draw threshold and whether or not you play at rest for long periods, a shore AC charger becomes essential. It simply becomes part of the price of admission for larger audio systems.

David
Earmark Marine

Razzman
05-24-2011, 08:10 PM
So for those with the ProMariner Pro Sport 20, when the batts are fully charged is there only one (1) green ready led lit? That's what mine's showing now along with the blue power light. The manual is pretty vague on whether it's one green for each batt or one total.

cab13367
05-24-2011, 08:59 PM
So for those with the ProMariner Pro Sport 20, when the batts are fully charged is there only one (1) green ready led lit? That's what mine's showing now along with the blue power light. The manual is pretty vague on whether it's one green for each batt or one total.

Yes, one green light indicating that both batteries are fully charged.

Razzman
05-24-2011, 10:26 PM
Awesome Al! Thanks

rdlangston13
05-25-2011, 03:13 PM
Well good news. I now have a new storage unit that does have electrical outlets so it looks like a battery charger is in my near future. Reckon I'll pick up an additional stereo battery while I am at it

WaterBullDawg1980
05-25-2011, 03:38 PM
From my limited reading thus far, it seems to me like it would make more sense to only buy a dual bank charger as opposed to upgrading your alternator if you have a semi serious stereo (3 amps, tower speakers etc) correct?

Newty, I think you had said you had upgraded your alternator. Did you also add the dual bank charger? I couldn't remember.

Sounds like I may need to do this. I haven't had a battery problem before, but my stereo is about to get a slight overhaul and will be using more power than in the past. I have two batteries already, but possibly will look at getting a third. Any rule of thumb as to when may be the right time to do this?

cab13367
05-25-2011, 07:36 PM
From my limited reading thus far, it seems to me like it would make more sense to only buy a dual bank charger as opposed to upgrading your alternator if you have a semi serious stereo (3 amps, tower speakers etc) correct?

Newty, I think you had said you had upgraded your alternator. Did you also add the dual bank charger? I couldn't remember.

Sounds like I may need to do this. I haven't had a battery problem before, but my stereo is about to get a slight overhaul and will be using more power than in the past. I have two batteries already, but possibly will look at getting a third. Any rule of thumb as to when may be the right time to do this?

If you have AC power where you store your boat, then the more economical solution is to go with an onboard dual bank charger. Just plug it in once you put the boat away and youíre batteries will be fully charged next time out. If you donít have AC power, then a larger alternator will help ensure that your batteries are getting charged as much as possible when the engine is running since they wonít get charged any other way. Even still, the batteries may not get fully charged depending on how much you run your boat vs play the stereo at rest.

As far as three batteries vs two, that will depend on your usage habits. If you sit at party cove for several hours at a time with your stereo cranked up, then you will probably want two stereo batteries to ensure you donít run out of juice. Otherwise, you can probably get away with just one stereo battery.

In my case, one stereo battery probably would have been just fine but we go on several 3&4 day trips each summer where we donít have access to AC power at night. Since we play the stereo at rest quite a bit, the batteries are not getting fully recharged from just running the boat so they could become discharged by the 3rd or 4th day. This exact scenario happened to me two summers ago. So thatís why I decided to go ahead and add a third battery. The cost to do so is not significant Ė about $100 all together in my case Ė so it was worth it to me.

The above also depends on what class amps you have (class D are more efficient than the typical A/B) and what load your amps are driving (a 2 ohm load requires twice as much current as a 4 ohm load at the same output).

Thatís my take on it anyway.

Al

WaterBullDawg1980
05-27-2011, 12:10 PM
Thanks Al! This helped clear things up for me.

WaterBullDawg1980
05-27-2011, 12:18 PM
Razz, What did you get your charger for if you don't mind me asking?

I am doing a bit of shopping and the best deal I have found thus far is $139.99 with free shipping. Unless I went with a refurb and then they have them for around $100.

This is for the 2 battery, 20 amp model

Razzman
05-27-2011, 01:24 PM
I went refurb on ebay, ChargerGuy. Real good to work with and 90 day warrenty. works flawlessly.

WaterBullDawg1980
05-27-2011, 02:11 PM
Yup thats who I saw on there. Good deal. I'm going to pick one up.