Z axis accumulating negative error (Resolved)

[martyscncgarage]

Just the one thread on this issue. I added a blurb about it to my machine thread based on your recommendation.

My machine is functioning. I still feel there’s an inherent issue with DYN4 connected to the open collector outputs.

Thanks!
Marty

[lavrgs]

Thank you guys so much for pointing out the obvious!

I homed the machine. I use the DYN4 ZRI pulse for as accurate homing as possible with what I have. Then I ran the following g code. Slow moves at 25 ipm.

Code: Select all

g01 x2 y2 z-1 f25
g04 p1
g01 x28 y13.5 z-5 f25
g04 p1

g01 x2 y2 z-1 f25
g04 p1
g01 x28 y13.5 z-5 f25
g04 p1

g01 x2 y2 z-1 f25
g04 p1
g01 x28 y13.5 z-5 f25
g04 p1

g01 x2 y2 z-1 f25
g04 p1
g01 x28 y13.5 z-5 f25
g04 p1

g01 x2 y2 z-1 f25
g04 p1
g01 x28 y13.5 z-5 f25
g04 p1

g01 x2 y2 z-1 f25

I have a significant amount of lost steps:

Capture22.PNG


I'm open minded about it being noise or some other explanation.. however, my experience last year taught me that the DYN4 drives do not like to work with the screw terminals. Yes, I'm using DMM's expensive cable made for this purpose. I will be removing the resistor and connecting +5vdc to the power supply and step/direction to the DB25. I bought a DB25 break out board when I ordered everything in for this conversion. I'll report back.

I'm having similar problems on a Tree J325. I'm using the DMM cables - is the resistor easily removed? In the picture I'm using the individual wires from the DMM cable but I have a breakout board so it should be a simple fix...

[ShawnM]

This is interesting to read. I am retrofitting a machine right now with the new DYN5 drives and the new drives have separate 5v pins as well as separate 24v pins for step and direction. I don’t know if the DYN4 is like this or not. I’m using the 24v pins and wiring them to the Acorn headers. I am making my own cables without any resistors. I have bench tested basic movement with the drives and motors and I just started installing everything into the machine now. Hope to do some testing right after the holidays. I’ll report back on this.