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Jeff Morris
 
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Default Electric power system for a small sailboat?

The Mercury 5 hp "classic" has an optional alternator, maybe yours is already
fitted. The spec says:

"Alternator Amp: Optional 4-amp lighting/2-amp charging"
http://www.mercurymarine.com/mercury_5_classic

If you have to buy anything, consider a small solar panel first - that would
likely keep it topped up all the time, and will be useful in the off-season.

Get a handheld VHF. The builtin requires an antena and will be useless if the
cable or antenna breaks - an easy thing on a small boat. Unless you rig a
masthead antenna, your range won't be that much greater than a handheld.

A small Fishfinder, like a Ray 265 is a great depthsounder, with a consumption
of 2 Watts (4.5 with backlight on) so it can run all day on a few amp-hours.
You can glue a transom mount to the inside of the hull. People may suggest
fancy setups (mineral oil tubes, etc.), but for a thin glass hull none of that
is needed, just find a flat spot, and glue it in. If the "glue layer" is thin,
then silicon can be used - you might try that first anyway just to see how it
works. A more solid glue, like epoxy, is slightly better but permanent. And
why even consider mounting on the transom? - for a small sailboat you want the
sensor as far forward as possible.


With LED running lights, and a battery powered camping "lantern" down below, you
could probably go a whole season on a 100 AH AGM battery.



"Jim Thompson" wrote in message
...
On Wed, 04 Aug 2004 12:58:45 GMT, wrote:

For a 17 foot boat used as you describe, you don't need much of
anything. Buy a decent quality deep cycle (not dual purpose) 100 AH
battery, and don't worry about all that extra stuff. You don't need
it. Really. Your outboard will keep things topped up with little
trouble. Even your need for shore power is highly questionable. You
really don't have much of a load, there at all.


Thanks. How does one rig a Merc 5 HP 2-stroke to recharge the
battery? Is there simply a way to tap into its stator output?

Jim