Re: [CAD_CAM_EDM_DRO] Gecko Heat Sink

Hi Jon,

Still seems terribly hot, my dial thermometer only went up that high.
The motors are too small for xyz axis drive, might get by for the rotary
table. I just wanted to use them for test.

What I am trying to do is get enough steps/sec out of my '366 Celetron.
With Mariss' new G201 drivers, the steppers run smooth, but at 10 uStep,
I can't spin them up very fast! Was there a thread on step multipliers,
about a year or so ago? I haven't found it yet in my archives. Can EMC
generate these high step rates?

Alan KM6VV


Jon Elson wrote:

>
> Alan Marconett KM6VV wrote:
>
> > Hi Joe,
> >
> > How warm does the heat sink get? Mariss can probably give you a formula
> > to calculate the heat sink thermal resistance needed at various
> > currents/voltages. A lot like ohms' law, you have a certain amount of
> > heat, and you must conduct it away to keep the temp below the rated
> > limits.
> >
> > My heat sink is cool, it's the old Superior Electric M062 motors I'm
> > worried about! 1.9A 4.7V, series connected, I selected 2A drive (do I
> > need to derate by .707?), and they get quite hot (over 130F)!
>
> This is in the normal range for steppers. Assuming 70 F ambient, that is
> a 60 F rise, or 33 C. The motors are likely rated for 40 C from a
> higher ambient.
>
> > So I
> > think these old motors may not be suitable! They're only 60 oz/in
> > anyway, I don't have new bipolar motors yet!
>
> Ugh, that may be a bit waek.
>
> Jon