Encoder wiring

[balsaman]

It's the same length as the y and shorter than the z.

I replaced the parallel cable, and took the cover off the encoder and blew air threw it. It's much better now. In 600 1" moves I was out 10 thousands. That is a lot better than 50 in 200 moves. These moves were all at 100 ipm. (I tried it at 10 ipm and was also losing position). The motors sound smooth. Get the odd hickup but I think that is turbocnc. I get the same error running Mach 1.

Question. My leadscrews are 6 tpi. That makes a crazy number for steps per inch with my 300 count encoders. Rounding errors should not acumulate should they? I would think not, since any error in one direction should cancel when the axis returns.

I am sure it's a problem with the encoder. I am going to take it apart, clean the glass disk, and put it back together. While I am at it I will see if I can find some cable with individually shielded pairs.

BTW, the drive isn't faulting anymore either. (at least not in the last 1500 1" moves)...

Eric

[balsaman]

Should the Step pin state be Active high or Active low in the Turbocnc setup for the geckodrives?

Eric

[sol]

Active high

[balsaman]

Thanks Sol.

Changing the setup from active low to active high seems to have eliminated the last of the error. I guess I was loosing one step every time it changed direction.

Now I need to put it all back together and see if I can maintain the accuracy. Still not sure which fix fixed it, but the biggest improvement happened when I blew air through the encoder at the glass disk while it was running. Funny, because it looked pristine inside the dust tight encoder enclosure. Never argue with success I guess....

Eric