On Tue, 01 Jul 2014 16:09:44 -0500, Jon Elson
wrote:

Tim Wescott wrote:

A client just asked me if I knew of any testing house that had a
dynamometer suitable for testing their stuff.

We're looking at something that can accurately measure torques from 0 to
about 100 N-m, at speeds from 0 to 80 RPM or so. Something suitable for
a full-race 502 is probably out of place here.

If you know of such a place, or if you have suggestions for where to get
or make an affordable dynamometer that's accurate to +/- 5 N-m or so, let
me know.

For smaller cases like this, a DC permanent-magnet brush motor can make a
VERY good dyno. A resistor bank and an ammeter are the other things you
need. A shunt-wound motor is even better, as you can vary the load
with a small rheostat or an adjustable DC supply.

Jon

Yes. A DC motor would apply load torque at any speed, and the current
is a pretty good indicator of the torque, with a bit of correction for
the actual speed maybe.


--

John Larkin Highland Technology, Inc

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com