Re: lb/in to oz/in

I would assume that they are not 14lb-in but 14 Nm, thats a different
story, 1 Nm = 141.6 oz-in, that would mean 1982.4 oz-in, you cant
compare these motors to any stepper, steppers would never have that
kind of torque at high speeds.
Check the plate, im pretty sure they ar 14Nm
Cheers

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Jon Elson <elson@...> wrote:
>
> John Dammeyer wrote:
>
> >A motor that provides 14lb/in torque applies a force of 14 lbs 1"
away from
> >the center of the shaft. With 16 oz per pound that's 14*16 or 224
oz-in of
> >torque.
> >
> >John Dammeyer
> >
> >
> >
> >>-----Original Message-----
> >>From: CAD_CAM_EDM_DRO@yahoogroups.com
> >>[mailto:CAD_CAM_EDM_DRO@yahoogroups.com] On Behalf Of danieltmedlin
> >>Sent: Wednesday, May 31, 2006 6:38 PM
> >>To: CAD_CAM_EDM_DRO@yahoogroups.com
> >>Subject: [CAD_CAM_EDM_DRO] lb/in to oz/in
> >>
> >>
> >>I have two 14lb/in, 100v, 34 amp, 4000rpm, and servomotors. What is
> >>the oz/in equivalent?
> >>
> >>What would be the closest equivalent in a stepper motor?
> >>
> >>
> Something doesn't register right here! this is a 100 * 34 = 3400 W
> motor, equivalent to
> 4.5 Hp. 224 Oz-In seems WAY too low. First, I think the torque rating
> is continuous or
> stall torque, and at a much lower current than the 34 A, which must be
> the peak
> current (and torque) rating. The Ke is 100/4 (100 V/4.0 KRPM) = 25,
and
> so the
> Kt can be calculated as 25 * 1.35 = 33.75 Oz-In/Amp. At 34 A that
gives
> 1147
> Oz-In! Ahh, that sounds like a much more reasonable figure. And, the
> 224 Oz-In
> would be developed at 6.6 A, which might be the stall torque.
>
> These are killer motors, and there IS no equivalent stepper motor,
period.
> You can get 1200 Oz-In stepper motors, but that is holding torque,
at zero
> speed. The running speed is FAR less, and you'll never get a
stepper up to
> 4000 RPM under load. These motors can deliver full rated torque at
nearly
> the full speed (depending on power supply voltage).
> Are these SEM motors? Those numbers look slightly familiar.
>
> Jon
>