Day Brown wrote in a message to Jock Rogan:
 -=> 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. 
DB> But, even when I tried a Briggs, and got 25 amps
DB> continuously, the alternators never gave nearly as much
DB> power at the same fuel consumption as the generators. 
DB> I also found that no matter how fast I ran the alternators,
DB> I could never get them to put out 25 amps *continuously*
DB> without seriously overheating.
   I've built a couple of Briggs-powered Chrysler Alternatored power
   plants.  I found out a couple of neat things:
   1)  The alternator doesn't care which direction you turn it
   2)  RPM doesn't need to have much to do with charging output.
       I got best economy at just above an idle - about 1000 rpm
       I'd think.  And the charging output is controlled by the
       Field Voltage.  I threw away the stock regulator real quick,
       and fed the Field through a variety of Field Resistors.  The
       best one I found was a 12V 20W bulb - the ones that look like
       ordinary house bulbs.  This gave me a constant 25A of charge at
       about 1000 r's, and I had light in the bus while I was charging
       the batteries at the same time.
    I never noticed any alternator overheating, and used the same generator
    for 3 years on the Baja, where we were spending 4 or 5 months a year.
    I was heavily into ham radio at the time, and spent a lot of each day
    on the air with my 120Watt rig.  The generator is still alive and well,
    although I don't use it any more.
DB> Finally, I found that the motor effect of a generator had
DB> enough moxie to electric *start* a 2-3 hp briggs, which at
DB> 300 watts of net output [@ 1/5 hp] was so lightly loaded
   Hard to beat that little extra, all right.  The military had gensets
   that used the generator as a starter during the war.  Homelites in
   Sherman tanks for instance, and they had a portable that did it as
   well.  We used them in the Canadian Army Militia in the '50's.  But
   if your Briggs is tuned right, and in good shape, a couple of pulls
   will light it up, anyway.  And if you use a good one, like a Honda,
   starting is never a problem.
   I use a fuel-saving product called Pro-Ma GT5, which also makes
   engines start much more easily, at least in my experience.  That
   can be a help, too.  Check out the web page:
   www.angelfire.com/biz/snwvlly/  for more info on that.
Best, ps
--- timEd-B10
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