Dynomotion Forum

Greetings,

Checking to see if anyone has had good success with Leadshine stepper drives. I am using 6 closed loop mode with encoder feedback directly into the KFlop. I am looking a the model below and see that the voltage requirements are:

"Direction signal: 5V signal, differential input. High input is 4-5V, Low input is 0-0.5 V. Minimum pulse width = 2.5 µs"

https://www.automationdirect.com/adc/sh ... ves/dm556e

These are going into an OEM machine, and I am looking for the best reliability possible.

In the past I have used KStep boards in "CL Step" mode. I would like to keep doing this but Leadshine has "Anti Resonance" features built into the drive.

So Three Questions:
1. Would I have the best luck running on "Open Collector - Step/Dir" or "LVTTL - Step/Dir" mode?
2. No need for the IR filter anymore because leadshine is taking care of resonance? This would mean deleting all of the IR filter values when configuring the axis?
3. Anything else I should be considering when using a 3rd party stepper drive with the KFlop closing the loop with an encoder?

- NO NEED FOR THIS STUFF?? (never really knew what it meant anyway )
ch0->iir[0].B0=1;
ch0->iir[0].B1=0;
ch0->iir[0].B2=0;
ch0->iir[0].A1=0;
ch0->iir[0].A2=0;

ch0->iir[1].B0=1;
ch0->iir[1].B1=0;
ch0->iir[1].B2=0;
ch0->iir[1].A1=0;
ch0->iir[1].A2=0;

ch0->iir[2].B0=0.000769;
ch0->iir[2].B1=0.001538;
ch0->iir[2].B2=0.000769;
ch0->iir[2].A1=1.92076;
ch0->iir[2].A2=-0.923833;

Thanks!

Scott

Hi Scott,

I am looking a the model below and see that the voltage requirements are:

"Direction signal: 5V signal, differential input. High input is 4-5V, Low input is 0-0.5 V. Minimum pulse width = 2.5 µs"

https://www.automationdirect.com/adc/sh ... ves/dm556e

These are going into an OEM machine, and I am looking for the best reliability possible.

KFLOP doesn't strictly meet those voltage requirements. To meet the specifications an external driver would be needed.

The Timing should be ok. Its best to use CW/CCW (or Quadrature) whenever available as it eliminates most all of the timing issues that exist with Step/Direction modes. But it seems that model doesn't support any of those.

1. Would I have the best luck running on "Open Collector - Step/Dir" or "LVTTL - Step/Dir" mode?

Open Collector mode normally works best. It should provide a High input of more than 4V when KFLOP is sinking to GND. But the Low Input would be greater than 0.5V. See the circuit below that shows clamping to the 3.3V Supply. This results in approximately:

5V - (3.3V + 0.4V) = 1.3V

Because the LED in most opto couplers require at least 1.4V to begin to turn on this usually works ok even though not meeting specification.

2. No need for the IR filter anymore because leadshine is taking care of resonance? This would mean deleting all of the IR filter values when configuring the axis?

Not really. Closing the position loop in an optimal manner will likely still need some filtering. Anti-resonance and closing the feedback loop are somewhat independent. Usually a 2nd order Low Pass filter (~100Hz Q1.4) helps stabilize the control loop. See also here.

HTH