Re: [CAD_CAM_EDM_DRO] Treadmill motor / PWM vs .SCR

On Sun, 12 Nov 2006 14:19:15 -0000, you wrote:

>Thanks Mark,
>
>I think if Les Newells' has been in use for a few years it's
>worth a try. Like you say, the motors have many other uses.
>
>Which invites a new question PWM vs SCR.
>
>What's your view?
>

I'm running a US made "treadmill motor" as a spindle motor on an SX3
mill, it says on the label 2.75 HP, but I've yet to get it draw anything
more than 12A or so. Says 21A at 110V on the label.

The brushes are 180 degreed to the armature and the motor casing,
despite this it's 1000 rpm down in "reverse" to it's normal 5700 rpm. at
100V. (It's continuous rated voltage) It has 12 windings on the
armature. It's "coggy" at less than 500 motor rpm. It's had an encoder
fitted and tried as a servo and failed. It generates a lot of heat and
has to be fan cooled.

Works OK in it's present use linked to a KB240 speed controller with a
2:1 reduction to the spindle.

YMMV.

Steve Blackmore
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