On-board chargers and cranking battery

[Mark Hofman]

I brought this up in another thread. I have a dual bank charger, which was connected to both the cranking battery and the trolling motor battery (by the rigger, I should add).



Wouldn't using the onboard charger damage the cranking battery? Doesn't the big motor do the recharging on that battery?



Was I right to disconnect it, or doesn't it matter?



Mark

 

[Sam Elkins]

I have the Guest single bank charger and bought a two bank Guest because I carry two trolling batteries so I just use the single bank for the starting battery and the two bank connected to the two trolling batteries. I use them as 12v so I also have a selector switch to get even use from both batteries. It doesn't hurt the battery as these on-board chargers know when the battery is fully charged and shuts off. This way if I don't run the big motor enough to keep it charged the on-board charger does it's job.

 

[TrepMan]

I've got the Guest charge pro and it is hooked up to both the trolling and cranking batteries as it is designed. Sue D. from Guest checks this site and will be able to answer any of your questions, you can also e-mail her at [email protected] .

 

[Sue DeLelys]

Mark,



Most onboard chargers are designed to be hooked up to either a trolling or a cranking battery. Some chargers can be damaged by having only one output connected to a battery. My best advise is to check with the manufacturer of the charger on your boat.



Have a great day!



Sue D.

 

[Tom(fishfafun) Lutz]

Mark,



Can't hurt the cranking battery to charge it a little but you can boil the water out of it if you charge it too long or too much......if you use your boat a lot you shouldn't need to charge the cranking battery between trips (at least once every 2 weeks or so). If the manufacturer says both sides of the charger need to run, then I would suggest installing a back-up trolling battery and hooking up switches to be able to use either one and hook up the charger to that one. Use large gauge wire to handle any amp problems.

I had a Ranger Dualpro hooked up to charge any 2 of my 3 batteries with switches and had no problems with it.



Tom(fishfafun)

 

[Gary Taylor]

I have the guest 2613 that is a 3 bank charger. It charges and maintains all 3 battery's. At 90 percent charge it trickles and then just maintains the cranking battery. It says it won't over charge.