Servo Driver Plasma Retrofit

Thank you so much.  I was able to create a 7i97t config.  No errors on starting or shutdown.  The 7i97t stays connected.  

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Is it possible to use stall force tolerance for z axis home and detecting the sheet metal in qtplasmac?  I will add a floating head and a z home switch if its not possible.

Hi kn612,

Were you able to get motion with your analog servos as well? PCW was kind enough to send me a 7i97t for testing as well. I will make a pull request to add it to 2.10/master when we confirm it.

kn612 wrote:

Is it possible to use stall force tolerance for z axis home and detecting the sheet metal in qtplasmac?  I will add a floating head and a z home switch if its not possible.
 

I'm not sure that could be done using analog without writing a custom component, but I'm no expert on analog.   In my experience you want some kind of floating head so that if the metal tips up or something it will stop the machine plus you can use it to probe the work height.  I haven't tried it yet but you can also do ohmic sensing to detect the material + float as backup.

I will add a floating head for initial height and a z max limit then. I am going to try and use the original hyperthem vdc3 board for ohmic and divided voltage.  Looking at pncconf it looks like I can use the ohmic enable output and input with the vdc3 board to do an ohmic circuit. 

I can get motion on all axis now with the analog servos and 7i97t on qtplasmac.  I am having a hard time getting them tuned.  When enabled they lock in pretty hard and the axis will jump.  The lower P Proportional value parameter the more they jump.  Around 100 they move the least amount (1/16 inch) on enable.  Changing anything else from 0 makes it worse.  I think the settings on the servo driver themself are causing issues. Going through the manual for these schneider lxm05ad10m2 drivers but its over my knowledge level.  

I am also reading up on Hal oscilloscope.  This is all new and challenging.  Ive only used steppers motors up to this point

Can you post you current hal/ini files?

Note that tuning a velocity mode servo is largely a matter of setting FF1 correctly.
 
Here's an older velocity mode tuning guide:

gnipsel.com/linuxcnc-old/tuning/servo.html