[daconfusion]

I have a new conversion for g0704 to 3 axis CNC with Kelling NEMA 23 steppers (570 oz-in, 5 A) for X and Y axis and NEMA 34 (906 oz-in) for Z.

I have installed AMT-102 encoders on the X and Y axis with 2048 counts (max). The Z axis is a US Digital encoder factory set to 5000 counts/rev.

I used the WiKi to perform initial sanity checks and tuning. System is operating in Encoder and Step_CL mode.

The issue:

When I move to Mach3, one axis suddenly jerks in jog mode and then triggers a disable. I then return to the Executive software, where same issue happens. Looking at the plots, it is obvious that the encoder is no longer working.

After removing power to Kflop, and re-powering, the encoder returns to a functional state (AMT 102 for x axis).

This seems to be an issue linked with communicating with Mach3 and not due to faulty wiring (at the moment).

I noticed that the hardware version is 4.33. I just bought the Kflop a few weeks ago. Is this a software bug that could be fixed with new a flash?

If this is a Mach3 setting error, I matched the tuning parameters from my initial exercise for V and A. V was adjusted to be units/min instead of units/sec.

I left the pin settings to be 0 0 0 0 (A A- B B-) under encoders for Mach3, no avail.
I disabled encoder in Mach3, that doesn't fix the problem.

Is this a pin/port setting mistake for encoders? I suspect the violent jerk and disable is caused by encoder not responding and then a fault is triggered.

Y axis occasionally does this behavior, but the issue is consistent with X.

Thank you!

[TomKerekes]

Hi daconfusion,

A common problem is to inadvertently configure a Mach3 Output to drive the same IO bit as one of your Encoder inputs.

See:

Various M Codes may be used within Mach3 to activate IO bits on KFLOP. Note Mach3 typically defaults after an initial install with Output #1 enabled for spindle control on Pin0 (as shown below). Bit 0 is often used on a KMotion board as an Encoder input. Having Mach configure the IO bit as an output will cause the encoder to be inoperable. Disable the output if this is the case.

From Step #6 here:
Mach3 Plugin + KMotion

HTH
Regards

[daconfusion]

Thank you so much for QUICKLY responding.

I believe you have addressed my issue. I am working on generating a demo (ghost) run for cutting now. As you can imagine, this moment (first potential chips) is very exciting.

I will be following up with tuning help. I need to understand how to properly "excite" the system to generate meaning full Bode plots, and hopefully take this data into MATLAB in order to employ various continuous and discrete techniques to specify P I D as well as the various filters. Fortunately the WiKi helped me avoid this obstacle to getting a respectable tune online. But learning the control theory and what that means is my final goal.