Replacing failed Guest Charge Pro 2722-B on-board battery charger

seasick

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I also have difficulty fully understanding the concept as well. Each charge lead has a separate ground to the negative terminal on the battery itself. A total of eight leads. My thought is if you treat the battery as a load on the charger it will have resistance, some degree of capacitance and some degree of inductance. These new chargers are simply not fixed DC output. I believe they do a pulse DC which could be thought of as pseudo AC but not sinusoidal. Given that, there is a big difference between two parallel resistors and parallel capacitors or coils. I have taken a number of electrical engineering courses up to circuit design, but that was years ago when we drew on paper and used a slide rule to calculate circuit parameters. Things have come a long way.
The separate ground leads makes it easier for me to understand how that arrangement can work. By sensing condition using both of the battery terminals, all the external variable like voltage drop across jumpers is eliminated. In addition, using pulsed charging the voltage and current states over short periods of time probably enables the charger to more accurately determine status as opposed to a simple voltage measurement.
It's interesting technology.
 

DennisG01

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You made me smile. I just went through this a few months ago and although I was sure I noted what hole or indentations the various cables and hoses were in, I just couldn't get things to fit. Determined, I started over maybe ten times and after an HOUR all the parts lined up. next time, I guess I will have to number all hoses and cables and make a good sketch of what was where
:)
 

DennisG01

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Each charge lead has a separate ground to the negative terminal on the battery itself. A total of eight leads.
Except this isn't true - or at least it isn't always true. For example, the ProMariner set up is grounded only to the main negative bus bar. There are no negative leads going to the batteries, only positive. I'm not sure if that helps or hurts in your and Seasick's conversation... ;)
 

wspitler

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Except this isn't true - or at least it isn't always true. For example, the ProMariner set up is grounded only to the main negative bus bar. There are no negative leads going to the batteries, only positive. I'm not sure if that helps or hurts in your and Seasick's conversation... ;)
My pro mariner has a ground for each battery. It does not use a common ground. I believe it’s the tournaments version.
 

seasick

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I have read articles about charging 12v batteries set up in series to provide 24, 36 etc voltage. In those cases, you can charge each battery with a 12 volt multi-bank charger as long as each bank has a separate ground. So depending on the application, separate isolated grounds for each bank are needed.
 

DennisG01

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My pro mariner has a ground for each battery. It does not use a common ground. I believe it’s the tournaments version.
That could be - my expereince with Pro Mariner is with the ProNautic series that I mentioned above. With that, though, I actually have quite a bit of experience - not just on my own boats, but also the few hundred that have come through the shop with that setup. But I have zero experience with the Tournament version. My main point was just that not all chargers use individual negative leads.
 
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