C30 MKIII built in battery charger question..

[AXEL]

I just bought this boat last season. I have only used the shore power once. This boat has what I believe is a factory installed battery charger. My question is if I am using it to charge the batteries should I set the battery select switch to one and then switch to the other or leave it on both?

 

[LakeShark]

Normally you would leave it on both. That way you equalize the charge across both batteries. Same is true when running the engine to charge you generally want it on both. Just remember not to switch it while the motor is running but I am sure you know that.

 

[Stu Jackson]

Axel, the answer is it all depends on how it is wired. Do you have a manual? Shorepower chargers used to be installed by the dealers, don't know when they switched to factory installed, but if it's a Charles charger it could be. Some chargers have multiple outlets, so you can turn the battery switch OFF and still use the shorepower charger. If you're interested in learning more about boat electrical systems, wander through this: http://c34.org/bbs/index.php/topic,5977.0.html

 

[Ron20324]

+1 to Lake. I would add both is okay if they are the same make/age/size. Some people are not comfortable having two batteries bridged together, as one battery going dead can drain and/or ruin the other. My boat is 200 yards away, so it is easy to switch one battery on to solar charge, give it a few days, then when on the boat next time, switch to another. Perhaps when you are satisfied both batts are charged, them have the switch on both. My 2 cents.

 

[kloudie1]

Typically, like Stu says, the charger is wired directly to the batteries so it does not matter what position the switch is in when using the charger. Best to trace the charger output to see where it goes.

 

[jssailem]

Best to trace the charger output to see where it goes.

I did that a week ago. Both interesting and messy. While solving one problem, found other lurking in the dark. Oh the joy of boating.

 

[LeslieTroyer]

I personally like using a ACR (Automatic Charging Relay or variant) - works when charging from shore or the alternator, and keeps the banks separate as needed. I don't have an "off" switch on the house bank (unless you count the 250A breaker) - even there I have a separate fuse bank before the breaker for the 24x7 devices like bilge pumps.

John - sorry I missed you last week - hope you stayed warm. The more I dig into my wiring the more I feel like I need to do what you just did and trace everything and remove unused runs. I could probably save 100lbs