Isolating the outboards

cemiii · Posted: Tue Jun 23, 2009 6:26 pm Post subject: Isolating the outboards

I have a 2 bank battery system with a combiner for charging. My 90 etec is isolated on the #1 battery. Almost everything else runs off the #2 house bank.

I have a 9.9 Johnson Kicker with e-start and 6A alternator. Can I just run it off the house side (so I don't have dueling alternators) or am I still running a risk to my electronics with the small alternator? Do I need a second switch for starting the kicker? Thank you,

Chris

matt_unique · Posted: Tue Jun 23, 2009 8:14 pm Post subject: Bats

Perhaps I'm missing something, but do you have two bats connected to one selector switch? Meaning, can you choose 1, 2, or Both? If yes, I would always have the switch set to both so you're charging both bats while underway. When on the hook, switch over to your dedicated house bat.

Captains Cat · Posted: Tue Jun 23, 2009 9:12 pm Post subject:

I don't think you'll have "dueling alternators" unless you have both engines running at the same time.

Charlie

cemiii · Posted: Tue Jun 23, 2009 9:24 pm Post subject:

Matt, yes, that is how it is set up, but I always leave it on 1. There is a Yandina battery combiner between the #1 and 2 banks so that (I am told, and seems to be so) both battery banks are being charged whenever the system senses a charging source, no matter what position the selector switch is in (even off, as with a home battery charger).

What I am more concerned about is the possibility of damage to the electronics if I start the kicker without turning the electronics off first. I read this somewhere and it has me concerned, though I have not had any problems yet. [one of the dangers of reading too much!]

Charlie, you are probably correct on the dueling thing, but I can't find any articles on duel set ups where they run them off 1 battery or 1 switch because apparently something bad can happen if an alternator does not sense a load. Though I don't normally run them together, there have been times in combat trolling conditions or being blown into shallow water, where I needed more power to get out of T, and did start the big motor before shutting the kicker down.

Chris

Captains Cat · Posted: Tue Jun 23, 2009 9:34 pm Post subject:

What usually happens, if you have your electronics on, when the voltage drops at a start, the electronics sometimes will kick off. My Garmin 545S shuts down but the Raymarine E-80, 4KW radar and Depth Sounder stay lit off... Depends on the sensitivity of the unit I guess.

Don't think you can damage the electronics in this situation, if you got a voltage surge, maybe but undervoltage, probably not.

Charlie