I'm with you AE on this one. Same voltage drop * same current = same power.

If that's too much power (unlikely) then then the only way to beat this is
to use a digital speed controller (eg PWM).


"A E" wrote in message
...


Dave D wrote:

"A E" wrote in message
...
Dave D wrote:

"Robert Morein" wrote in message
...

snipped

In my experience with 12V fans,

They're 5V fans.

a series resistor works nicely, as does
running them from a stiff 6V supply.

A series resistor generates heat, diodes drop voltage and run
cooler..
They

So, you're saying with the same VI, a diode generates less heat than a
resistor???????????


Nope, see Sam's post. It will always drop a relatively fixed voltage,
regardless of current draw, so it is more efficient than a resistor in
this
application.

Dave

Makes no sense. You will simply not draw more current through that diode
than
with a resistor, because the load is the same... If you put a resistor in
series
with the fan, and the resistor happens to drop .6V (simple to figure out,
if you
can draw a load line, otherwise a bit of experimenting), the same amount
of
current will go through that resistor as through a diode... Same heat
dissipation in both cases. Don't you think?