Mad scientists, all!
Michael.Chamberland (23274MJC@MSU.EDU)
Sat, 04 Mar 95 20:19 EST
> > > He used a little 1" computer fan slowed down to a very slow
> > > speed with resistors to slowly diffuse the CO2 amongst his plants.
> > > It worked amazingly well and was completely safe.
> > >
> >
> > This bit caught my eye. One word of warning for people who may be
> > inspired to do the same. Be careful as to the sort of fan you buy. A
> > lot of the modern fans are "brushless" DC motors which do not respond
> > to lowering the voltage (this is what the resisitors are doing -
> > lowering the voltage to the fan) in any useful manner.
>
> This is not quite true. These resistors aren't meant to reduce the voltage
> on the brushless DC motor. They're meant to reduce the _current_ through
> the motor. Anyway, the result is that the motor will get less energy and
> will turn less powerfull (slower) until the internal and external friction
> match the energy level you provide.
Look here! Even electrical engineers can't agree about hard-science
matters of fan electronics! Now, should we be so quick to browbeat
taxonomists for inconsistancy in species delineation? :-)
Michael