Re: [CAD_CAM_EDM_DRO] Yaskawa Minertia brushed DC servo specs

snagglexr650 wrote:

>Hello,
> I just bought 3 Yaskawa DC brushed servos off Ebay. I'm trying to
>get an idea of what kind of volts/amps they will require to run at
>their maximum performance using Gecko G320's. Yaskawa's website has
>no mention of these small DC motors. All that I know is from the
>sellers description;
>
>Yaskawa Minertia UGRMEM-R02SAK0E
>
>56W, Voltage Constant 6VDC,/1000RPM
>

56 W is a very small motor. That is the continuous rating, of course.

>
>1.06 n-M PEAK torque, , 8.8A Peak
>
>.212 n-M constant torque
>
>3000Rmp operating, 4000Peak
>
>straight shaft w/ tapped center hole
>
>Encoder Spec UTOPI-200 shown above.
>
>We believe but are NOT positive that the 200=2048PPR.....
>
>
>Going by the voltage constant and rated RPM it 'appears' that they
>want 18V (3000RPM) - 24V (4000RPM). Geckos require a minimum of 24V
>don't they? Will 24V drive these motors to hard?
>
>

No, you probably will get very poor performance at 24 V. You have to
account for armature resistance if you want to be able to get near peak
torque while spinning.

>What about current, 8.8A peak, but what would I set the current limit
>to on the G320's?
>
>

As close as you can to 8.0 or 8.5 A.

>One final question, being a 200 count encoder, assuming TTL, wouldn't
>that be 200 X 4 = 800 ppr as the final resolution rather than 2048?
>I always thought you multiplied by 4.
>
>

Yes, if the encoder is measured in lines or cycles. If it is measured in
"counts", then you can't be sure whether it is really describing cycles or
quadrature counts. But, I seriously doubt it is a 50 cycle/rev encoder,
that is
just too low.

Jon