i am trying to figure out the best way to wire my batteries and charger into my boat. what i have is a pair of group 27s and i am adding a third group 27, i have a guest 3 bank battery charger, i have a perko a/b/off switch and a perko on off switch. i run a decent size stereo setup also. i am wondering if i want to isolate all 3 batteries with perko switches whether i run the pair off of the selector switch and the third one off the on off connected on the output of the selector or do i want to run the pair off of one side of the selector and the single off of the other side and then use either the on off between the pair to isolate them or maybe even a solinoid between them? any input would be helpful. thanks

I run two perko switches. One on each side. Port side only has one battery and runs one amp but ready to run 4 if needed. Starboard side has two batteries and two amps.

I wish this snow and cold would go away so I could finish my projects.

I couldn't resist. I wonder if this kit is available, I might need it before this week is over!

funny stuff randy! i must have accidentally made this a omaha only post LOL. i think i figured out how to wire this all up . i have the boat in a heated garage right now so i can actually work on it with our awesome weather

If you have a single engine boat, I would run to in Parallel on one side of perko, and the other on the oposite.

if you had twins, then i would have 2 perkos. and same set up.

unless you have a genny. then you want 3, so you can separate them all. or connect them

Thanks Josh, it doesn't hurt that it is the same model & color of Harley in my garage. I'm glad it didn't freeze after just firing my brand new engines!! Not sure how big your batteries are, I think I would dedicate 1 for engine only but have at least 1 other available for starting just not sure how to wire it. You will want to have a big alternator to keep them charged. 95amp? Let me know what you come up with. Randy

For my single engine, I have three batteries and added a second switch, same as the first ( 1, off, 2) Also if I wanted to add a fourth battery I could. Just connect the two "main" lines together. I always heard never keep batteries in parrallel as one will kill another if weaker. I then just hooked up my three bank charger to the back of each number on the switches.

I have a twin set up with two batteries. I bought a thing, sorry can not remember the name on it, but bascially you hook the third battery to this thing, and then hook it to another battery. The device will run the battery till it gets low and if you are stopped it will shut that battery off automatically so it wont drain the other one or two. Once engine is running it will charge up the battery again. Sorry cant rememember the name on it now. I bought it to hook my stereo to, and think its a great application for things like stereos and things you might run will stopped.

This is how I would do it (plan to do it if I ever get another battery hold down).

How I currently do it: