[Amps] Blowers

[Jim Strohm]

"Frank Ayers" <w2fca@qsl.net> asks

>A blower related question - I have a Dayton 4C006 blower. The
>published ratings for it start at a static pressure of 1/2 in
>and go up to 1.2 in. there is a note in the 0 inch static pressure
>column which says - "overloaded, do not operate under .5 in SP"
>I've asked my friendly neighborhood Granger dealer why that is
>and they have no idea. Anybody know?

Once you stall the blower, there's no airflow to cool the motor, and it
will overheat relatively quickly.

If you plot the product of air flow and backpressure you should get a graph
that's roughly parabolic, and ideally you'd want to operate near the peak
of the curve and above your minimum required backpressure.

From an airflow standpoint, Rich is right -- the blower's not too big until
it blows the tube out of the socket.  From an equipment reliability
standpoint, you want an appropriately sized blower.

Added benefits to having the right size blower?  It's quieter, more energy
efficient, and lasts longer.

But with the junk most of us use, "big enough" is all you need.

Jim N6OTQ