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PTO Acceleration / Deceleration time not correct

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I'm using USC-x10-B1 with UID0808THS high speed module.
I configured high speed module as PTO - Block 1 and left Block 2 set to OFF.
I set User Defined Units / Pulse ration 1:1
Jerk factor is set to 1 (trapezoid curve)

Target velocity: 60000 (pulse freq. 60kHz).

I'm seeing issues with Acceleration/ Deceleration time of pulse train. It doesn't match desired level and/or it's jittery (acc/dec in steps)

Attaching examples of Current velocity when PTO acc/decc time is set to 650ms (actual transition is 100ms and motor acc/decc way to fast) and when acc/decc time is set to 680ms (actual transition is 850ms and jittery and mot. acc/decc to slow).
This PTO behavior is clearly seen (heard) on stepper as well.

I tried to test with lowering the Target velocity, but issue persist. Also played with Jerk factor (increasing it to "S" curve as make the PTO response even steeper as expected)

Someone had simmilar issue in the past? Is this a HW limitation?

Thank you in advance!

PTO acc/decc time is set to 650ms

PTO Acc 650ms.jpg

PTO acc/decc time is set to 680ms
PTO Acc 680ms.jpg

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I wrote the post after few days of playing with this issue, but found the solution an hour later...  😄

Found out the soluiton
It was setting for Max velocity at HS block that was too high. 
PTO Speed up / down ramp is calculated between "MIN and MAX velocity" (which you set in HS block) and time you enter in Acceleration / Deceleration time tag (PTO Config).

PTO "Target velocity" has nothing to do with acc/decc ramp but only stops acceleration when it's reached.


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