-=> Quoting Jock Rogan to Charles Bowman <=-
 JR>... I think if you are using an auto alternator
 JR> you may want it closer to 1200 rpm. I think my old Morris generator
 JR> used to show life at about 900rpm. 
I usta have a waterwheel. hooked up to a delco truck generator,
it would do 25 amps all day.  hooked to an alternator, it would
do 8 amps till it fried 20 minutes later.  As you suggest, the
alternator needed much higher RPM.
But, even when I tried a Briggs, and got 25 amps continuously,
the alternators never gave nearly as much power at the same fuel
consumption as the generators.  furthermore, the alternators all
used ball bearings on the stator, and if the belt got to slapping,
would tear up within a week, whereas the generators all have a
sintered brass bearing on the pulley end, and with routine oiling,
would handle belt abuse forever.
I also found that no matter how fast I ran the alternators, I
could never get them to put out 25 amps *continuously* without
seriously overheating.
Finally, I found that the motor effect of a generator had enough
moxie to electric *start* a 2-3 hp briggs, which at 300 watts of
net output [@ 1/5 hp] was so lightly loaded they'd last years.
 
... Blinded by the fog of battle in the war of the sexes.
--- Blue Wave v2.12 [NR]
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