Parallel or float alternator outputs

"Hello,
I have a pair of 2005

"Hello,
I have a pair of 2005 Yamaha 225s. I'm considering a BEP marine switch cluster, which has two alternator inputs. Each motor has two alternator outputs. Is it best to parallel each motor's output or should I let the aux alternator output float unconnected?
Thanks,
Mark
Melbourne FL"

"Mark, I think if you dig in y

"Mark, I think if you dig in your owners manual you will find that ALL of your alternator outputs must end up at a battery to protect the integrity of the system.

Your particular model(s) provide two outputs (per motor), one for your starting battery and one for the assessory (house) battery and it keeps them isolated from each other so one doesn't drain the other.

But you shouldn't ever run without those leads terminated at a battery, since the battery acts as the capacitor on the system (and the power generated has to go somewhere).

So your easiest solution is to parallel both connections from the individual motor and treat them as a single input for your new Blue Sea set-up.

The other alternative would be to utilize only one of the lead pairs and connect the second to a terminal block on the engine - however, the only thing that would accomplish is a reduction in the number of wires coming from the motor back into the boat...."