"Dr. Hardcrab" wrote:

Again the controller issue. Has anyone ever seen a data sheet
for these motors?

Has anyone considered that the controller is built into these
motors, ...

http://www.nailor.com/pdf/ECM_1.pdf

http://www.enviro-tec.com/pdf/catalo...ormanceECM.pdf

The above two are more like sales sheets or flyers, not really data
sheets with pinouts and wiring diagrams.

But still, they confirm that the controllers are built into the
motors, and they can either be set to run at constant speed, or
constant air flow (not sure how exactly they can sense airflow), or
they can take a control voltage (2-10V) which is trivial to set up
next to a thermostat.

If I had one of those, I'd tinker with it to see if I could get it to
run off a DC supply. A DC battery backup would keep a motor like this
running during winter power failures. I bet there are some in the
plains and mid-west who know all about winter power failures.

"Most variable speed electronic devices, including the ECM
operate with a rectified and filtered AC power. As a
result of the power conditioning, the input current draw
is not sinusoidal; rather, the current is drawn in pulses
at the peaks of the AC voltage. This pulsating current
includes high frequency components called harmonics."

So these motors are likely to radiate RF/EM noise if filtering isin't
used (and given manufacturing price pressure I wouldn't count on these
having proper filtering).

And one more thing - the power utilities really like these non-linear
loads - NOT!

"ECM (tm)"

Someone trademarked "ECM" ? Are you kidding?

http://www.eere.energy.gov/buildings...ler_app8_7.pdf

Yea, I've seen that one before.