Strange battery charger configuration.

[agallant80]

OK I will list the setup before I get in to the question.

2 Battery banks each bank has a size 24 battery switch connected to a A-B-All-Off switch
ProNauticP1215 Charger

The ProNautics charger has the ability to connect to 3 banks. I only have two.

The ProNautics chargers has three outputs for the thee banks it can charge

I have two of the outputs connected but for some reason they are crimped togeather and attached to a larger cable that runs not directly to the batterys but to the A bank of the A-B-ALL-OFF switch so when using the charger it only charges the A Bank unless I set the switch to ALL

I cant imagine why at the factory they would do this, there has to be some logic to this. Its strange being plugged in to shore power to wake up with bank B dead and bank A fully charged unless I move the switch over to ALL.

Can I just rewire this thing so Lead 1 on the charger goes to Bank A and Lead 2 goes to Bank 2? or so bank1 goes to A on the switch and bank2 goes to B on the switch?

I am so confused why Bayliner would connect it this way from the factory. I have attached the image from the manual showing how to connect it to the battery banks.

 

[Georgesalmon]

Re: Strange battery charger configuration.

Can't answer your question about why its connected that way. But, I would redo it as shown in the electrical diagram from the battery charger people. That's how mine is connected, directly to the batteries not through your battery switch.

 

[agallant80]

Re: Strange battery charger configuration.

Can't answer your question about why its connected that way. But, I would redo it as shown in the electrical diagram from the battery charger people. That's how mine is connected, directly to the batteries not through your battery switch.

Yeah that is what I am thinking I just can't for the life of me figure out why they would do it this way. It is more effort to wire it like they did. The charger is right next the the batteries. It would have been way simpiler to connect it directly to the battries. It could not be accadental and the manual says to put the temp sensor on the house bank but on my boat its on bankA (starting) which is the same place the charger connects to on the switch.

 

[Silvertip]

Re: Strange battery charger configuration.

There is a logical explanation for this. Since you have two batteries but a three bank charger, two of the outputs have been paralleled to charge the battery with the highest deamand (the house battery or a trolling motor battery). That connection can go directly to the battery or to the applicable terminal on the switch. Electricity doesn't care because it essentially the same spot (the battery). The currently unused charger output can, and should go to the other battery or to it's terminal on the switch, whichever is closest. If this boat is new to you (but previously owned) who knows what the prior owner did. So to recap - put the two outputs on the house/troller battery and the single output on the starting battery. All bases are covered and the dual battery switch can be left in the OFF position when away from the boat. If the boat is actually new, keep in mind that that folks doing electrical work (assembly especially) are not exactly up to speed with that aspect of boat building so wiring can be a challenge. If things are labeled nicely anybody can make a plug/receptacle connection since they are generally keyed and therefore cannot be screwed up. Point-to-point wiring is quite another issue however. You had best know what you are doing and in this case they apparently didn't. If the three bank charger was standard equipment for the boat, it may have been specified to accommodate a 24 volt troller or two separate house banks plus the starting battery.

 

[agallant80]

Re: Strange battery charger configuration.

A generator is an option on this boat so I can see a charger with three banks. One for the house, one for starting and one for generator starting. In this case I have no idea what Bayliner was thinking. I don't see any advantage to having it connected this way. I only see disadvantages such as the switch has to be on to charge the battries, it will only charge both banks if the switch is in the all position, pull away from the dock and throw down anchor forgetting to take it off the all position is a great way to get stuck. I am going to go ahead and change how Bayliner configured it from the factory. There have been a few strange things on this boat like the charger. For example for some reason on my boat the mounted the AC pump above the water line so it always needed to be primed. I had to move it to below the water line.

 

[glenn property of pam]

Re: Strange battery charger configuration.

the charger is X amount of amps per bank so if you connect 3 batteries and say the charger is a 30 amp then each battery is really getting a 10 amp charge. now if you hook 2 banks to one battery it gets 20 amps charge and the other bank puts out 10 amps to different battery.
Now most people do not need to charge the motor battery as its only used for starting and is recharged by the alternator so they may hook all 3 banks to the house batteries for fast charging. There lots of ways to skin a cat so if the way it is wired doesn't suit your needs then just rewire it following the manufacture instructions. Some modern chargers are able to link and unlink the charger internally so if all your batteries are running 12v the charger will change the charge rate depending on the charge level of the batteries. This does require that all the battery negatives are connected together.

 

[agallant80]

Re: Strange battery charger configuration.

I put some more thought in to why they did this and the only thing I can think of is if I have a charger led hooked up to both banks and the switch is in the all position what happens? Was it to prevent this situation? I am considering leaving the configuration alone and just switching it to all when on shore power but what happens of bank1 has 1 battery and bank2 has two batterys?

 

[Silvertip]

Re: Strange battery charger configuration.

I put some more thought in to why they did this and the only thing I can think of is if I have a charger led hooked up to both banks and the switch is in the all position what happens? Was it to prevent this situation? I am considering leaving the configuration alone and just switching it to all when on shore power but what happens of bank1 has 1 battery and bank2 has two batterys?

Nothing happens with the switch set to BOTH. This places both charger outputs in parallel along with the batteries. Like I suggested earlier, put the charger leads directly to each battery and you don't have to worry about where the switch is set including the OFF position. The batteries will charge regardless where the switch is set.