BATTERY CHARGER

[Dr. Thagg]

i HAVE A C-25 SWING KEEL 1985. SHE HAS TWO BATTERIES, HOOKED IN SERIES BELOW THE PORT SETEE,> AND WITH A SOLAR PANEL THAT KEEPS THEM JUICED UP, THEORITICALLY.I WOULD LIKE TO CONSIDER A WIND GENERATOR OR ANOTHER METHOD TO CHARGE THE =BATTERIES WITHOUT USING SHORE POWER. i HAVE A 1995 9.9 JOHNSON O/B, ELECTRIC START, BUT IT DOESN'T CHARGE ANYTHING.ANY SUGGESTIONS APPRECIATED.THAGG

 

[Dan]

Go solar

But, first, calculate your usage so you know how much generation you need. If you live aboard, you'll need a lot. If you just day sail, you'll need little. I day sail and occasionally overnight, and I have used a 11 watt panel for four years and have only had to plug in to the shore once. However, I don't have refridgeration, vhf, vcrs, gps, etc. I run lights, and the stereo, but for several hours at a time and often all night.  You say the solar charger "theoretically" works. Test the thing to be sure. Do the batteries hold a charge? You need to do some homework, then you'll know the answer. Wind power is fine, but a mechanical device, thus susceptible to failure. Keep it simple.

 

[Ted]

A couple of options . . .

1) solar, like the previous post suggested. I use a 5 watt panel to keep a single battery charged. I barely use the batteries, so 5 watts keeps them topped off. If you use lots of battery power, then you may want 20 or more watts.2) Most motors of 10 hp and up can have an alternator added as an option. This would get you lots of amps on demand. The disadvantage of solar power is it takes sunshine and time to recharge. An alternator would get you the recharging power you need in a hurry.Regards,Ted

 

[Bayard Gross]

You might have an alternator on that Johnson

I think you may have an alternator on that Johnson. You can check by running a digital volt meter across the leads that connect onto your battery and see if if it puts out about 13 volts at a about half or three quaters top speed.If so, then the issue is that alternator is trying to charge two batteries at once (batteries in series), a task for which it is not designed and hence does not charge them up. It has the voltage, but not the amperage.An answer is to install a battery one, two, and both switch. Thus when you are under power, switch to either one or two and the engine should be able to charge that battery. Then switch to the other to charge that battrery. And then when you need extra power to start the engine, switch to both.

 

[Dick of Sylvan]

Series?

Thagg: Surprised you say your batteries are wired in series. Most small boats I've seen run electrical things on 12 volts, and usually use 12 volt batteries, and if more than one they are wired parallel to keep things at 12 v. If you use 6 v. batteries you would wire them in series to get 12 v. Anyway, your outboard's alternator may not be charging. My Honda once had a blown fuse under its cowling because of mis-wiring associated with change of boat ownership (red = positive to me, but previous owner had done it in black). Not sure if Johnson has fuse, but its worth checking. Even if working properly however, you have to motor a lot for it to be sufficient, necessitating a supplemental such as solar. Dick

 

[Dr. Thagg]

thanks

i'll look into the idea of the 9.9 johnson having an altenator that isn't working.thanks