Re: [CAD_CAM_EDM_DRO] Servos, Drivers etc.

camerashy44 wrote:

>I have finally decided on the servos for my mill conversion. They are;
>Reliance Electric DC Servo
>Micro 100 Series
>NEMA 34 Frame
>Model 0660-04-076
>Nominal Speed Rating: 1750 RPM
>Nominal Voltage Rating: 120 Volts
>Back EMF Constant, ke = 68 V/kRPM
>Torque Constant, kt = 5.75 lb-In/Amp
>Motor Body Diameter: 3.38"
>Motor Body Length: 6.5
>Shaft Diameter: 0.375" x 1.13" Long
>Integral Encoder: Hewlett Packard/Agilent
>Model: HEDS-5505 A06
>500 lines per rev in quadrature, yielding 2000 counts per rev.
>Is there anything that I should consider with this motor that I may
>have over looked?
>I am assuming (and this is dangerous) that the Geko drives will not
>have enough voltage to run these motors at their maximum. Am I
>correct?
>

Yes, and as these are low-speed motors, you may find this a limitation.
But, they are strong, so you probably don't need to gear them down.
With 70 V you'd get ~ 1000 RPM. With 1000 RPM on a .2 pitch screw,
you get 200 IPM. Is that too slow? At that rate, you need 33 K step pulses
per second 9with your 2000 count/rev encoders). Will that be your
limiting factor?

You will need a serious power supply, if you want to get full torque out
of them.
(I don't see a peak current rating there.)

Jon