Re: lb/in to oz/in

Or 14 FOOT pounds...

Ballendo

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Fernando" <fer_mayrl@...>
wrote:

>
> 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
> >
>