Re: Servo Operating Temperature?

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Jon Elson <elson@p...> wrote:

>
>
> mmurray701 wrote:
>
> >I finally have my mill converted to servo control and am just
> >wondering how hot servos generally run. After being run for about

1-

> >1.5 hours the Z axis motor is slighly hot. You can still keep

your

> >hand on it no problem but it is a little hot. I didnt get a

chance

> >to run it any longer than this yet.
> >
> >They do have a sticker stating to use caution when touching them
> >because they can get hot, but i'm just wondering how hot is too

hot?

> >
> >The setup is Electro Craft E-543 servos running off G340 drives.

The

> >gain/dampening knobs are just left at factory settings. Current
> >limit is set at about half, thats all the torque I need. Thanks

in

> >advance.
> >
> >
> This doesn't sound too bad. These motors can generally dissipate
> a fair amount of heat. The Z axis generally has the problem of

constantly

> supporting the weight of the moving part, thus a constant current

flow

> through the motor. One way to fix this is to put a belt reduction

ratio

> on the motor, so it doesn't have to deliver as much torque as it

would

> with direct drive.
>
> Jon

Hi Jon,

Thanks for the quick response. I am running a belt reduction of 2:1,
this should be more than enough because its just a mini mill and the
leadscrew is very mild pitch (20tpi).

I see what you mean about the Z axis putting out more heat.
Strangely enough even the Z axis stepper got hotter on my old
system. Not quite sure why a stepper would. Maybe I had the current
limit just slighly higher on that axis.

So you think i'm safe? If I can keep my hand on it then it shouldnt
be ok? Thanks.

Mark