G' Day, Day
On (13 Aug 97) Day Brown wrote to Alec Cameron...
 DB> They do make generators for mission critical stuff like
 DB> ambulances.  Lots of rural junkyards don't recycle stuff so
 DB> fast, so still have generators.  the standard delco will do
 DB> 20 amps -continuous service-.
Good point. I would have thought that for ambulance duty, an inverter would
be the choice for the small AC loads normally required.
 DB> discard the volt regulator, put in a 2-3 ohm 10 watt resistor
 DB> on the fld winding, and you can get efficiency way beyond what
 DB> an alternator will get you.
Volt regulator is not a cause of inefficiency. By substituting a 2-3 ohm
resistor, the voltage will tend to wander up and down with shaft speed or 
oad
current variations. Wouldn't it be smarter to fiddle with the volt regulator?
Feed it from a voltage divider for example so only a fraction of the supply
voltage will be "seen" by the regulator. That would result in the regulator
trying to achieve the higher voltage you might want to run at.
 DB> It will also 'motor' a 2-3 hp engine enuf to electric start it.
 DB> double the speed, and you double the voltage.
Yes but what if you have sensitive loads like tungsten lamps or electronic
devices also connected? Double voltage...... get your check book ready!!
Cheers.....ALEC
... Wunce i coodn even spll ingineer. Now i are wun!!
--- PPoint 1.92
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