Battery Cables:

[MACHTECH]

I disconnected my battery cables to remove the batteries to charge them. I didn't pay attention to which wire went where. I have 2 red cables and 2 black (with no markings). I assumed they went to the batteries red to pos and black to neg. Had aft battery all hooked up to both terminals. Had forward battery neg hooked up. When I went to install pos terminal I got a big arch. Manual says batteries are supposed to be hooked up in parallel with a jumper cable going from aft positive to forward neg terminal. I had no jumper cable when I disconnected the cables in the first place. It said that would give a 24 volt boost to everything verses a 12 volt. Do the red cables go to different things? Next time out to the boat (when it gets cooler) I going to see if the red cables go to different places. I hope I didn't fry anything with that quick arching which scared the crap out of me down in there with the gas tank!! Can anybody shed any light on to my dilemma ?? Red cables go to box on the aft engine room bulkhead.

 

[M24per]

What ski are we asking about exactly?

 

[mikidymac]

You are talking two different things.

Are your batteries 6V or 12V?

Parallel:
Both 12V batteries, #1 & #2 get connected with black wires from engine/electrical box to Negative on the battery. Red wires from engine/electrical box to Positive battery. System voltage will be the correct 12V.

Series (Wrong Way):
Black wire from engine/electrical box goes to the negative battery terminal of battery #1, positive terminal on battery #1 goe to the Negative terminal on #2, Red wire from engine/electrical Box connects to Positive terminal on battery #2. This will double the battery voltage so system voltage will be 24V You Will Fry The Electrical System at 24V.