On Tuesday 05 May 2020 20:17:45 Dan Henderson wrote:

> Slowing things down had marginal effect. Okay sounds like I need to by
> pass the optocouplers. Would you recommend I bypass all the encoder
> inputs as well as the PWM output to the MC2100 controller?

Only if it has opto's for isolation, they can effect to duration of the 
pwm playing hob with the speed linearity.  If the motor is "hunting", 
something else is going on.  The m2100 ISTR is the controller that came 
in the treadmill and its a very serious case of built by lowest bidder, 
I was not able to use it in anything I've tried. Control was extremely 
non-linear until I put a 47k resistor between linuxcnc and its summing 
point,  That helped but it was still flaky. Not to mention that all of 
its control circuitry is on the hot side of the power line and quite 
dangerous.

I am not a machinist, but a long retired broadcast engineer and a CET so 
much of the high power stuff comes out of my junk box. The psu for 
instance,  makes about 120 volts DC at a surge current of 20 amps, 10 
forever, way more that the 1hp motor I'd put on the back of a 7x12 lathe 
is rated for. Capable of getting 2hp out of that 90 volt motor. But it 
kept breaking drive parts once I had obtained one of the pico systems 
pwm-servo drivers.  So I've gone into the hal file and slowed the motors 
acceleration to something that doesn't break stuff any more. But that 
might explain why my troubleshooting is geared to the electronics, and 
possibly is different than what a real machinist might do to solve an 
identical problem.

Other than that it doesn't sound as if the opto's speed is your problem.  

So 2 other questions:

What to you have in the way of meters and oscilloscopes for 
troubleshooting?

Do you actually have LinuxCNC running well enough to try to control your 
motor?

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page <http://geneslinuxbox.net:6309/gene>


_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users

Reply via email to