battery charging with the outboard

[gershel]

Has anyone used a Flexcharge mod. NC 25A / 12 , or something similar, to control the charging voltage from a Yamaha 9.9, or similar type engine.
Marc

[WDfrmTN]

Don't think a solar/wind charge controller will work well for an engine-run alternator - different mode of regulation.

[mitiempo]

If the outboard has an alternator it will not need anything else nor benefit from adding anything.

[gershel]

I have gel cells, and I'm afraid of using un-regulated voltage

[mitiempo]

It is not unregulated, as well as being very low in output. The Yamaha 9.9 only has a 6 amp output with a built in regulator.

[timangiel]

There was a guy who posted a schematic diagram for a circuit you could build yourself for just that purpose. When I have more time I'll try to find it and post a link.

[hellosailor]

tim, an LM317 adjustable regulator (the 78xx or 79xx fixed regulators would do but I don't recall if they'd match a gel voltage) would be an easy DIY. All the manufacturers have spec sheets for this and the only addition would be using a power transistor to handle the output of the engine. The regulators typically handle 1.5A max by themselves, one power transistor could boost that to handle a 10A load. Again, the mods are in the spec sheets from all the manufacturers.

Marc, you really need to confirm whether you've got an alternator or a generator, whether it is regulated, and what the output is (volts and max amps) to know what your options will be. Generators and alternators are regulated very differently.