Prototrak Plus Retrofit with Mesa 7i77 & 5i25 cards

new2linux wrote: Andy, what can I say? I have read so many threads.
Todd, I am very thankful for you taking time to help!! Thank you!
the amps are AMC Advanced Motion Control, Brush Type, this is link to pic; forum.linuxcnc.org/media/kunena/attachments/21712/IMG_1001.JPG

www.a-m-c.com/wp-content/uploads/support...ual_Analog_Panel.pdf

this is a manual for setup.

thanks!!

Unfortunately that picture doesn't show the model# of the amp (They made lots of different ones), and that manual is kind of generic, covering lots of different models.

According to that manual you need the "specific drive data sheet" to know how to configure the switches on the drive to properly set the drive's mode and tune it. If you don't have that it can easily be looked up from on line with the drive's model number.

I suspect the drive is in "Duty Cycle (Open Loop) Mode" described on pg.14 of that manual (other drives might call this voltage mode). It is best described as somewhere in between torque and velocity mode. and should be a lot simpler to tune than true torque mode.

Tuning this drive in voltage mode should be mostly the same as tuning a Pico systems amp here is a very good tutorial.
wiki.linuxcnc.org/cgi-bin/wiki.pl?PWM_Servo_Amplifiers

If I'm guessing your amp model# right this should be the data sheet.
www.researchconcepts.com/Files/20a14.pdf

Many, many thanks for the input, I will be working in the suggestions offered!

Just as a side note I was unable to access the forum yesterday "all day" it just would request "reload" to go no where. I have reviewed the manuals for setup and tuning.

To keep all the information in one place this is a pdf from earlier thread. servosystems.com/pdf/amc/12a8.pdf This is not in order if you follow the sheet numbers. The amp is a 12A8E Advanced Motion Control, brush type.

many thanks!

Edit: Setup for "current mode" DIP switch are 1,2 & 4 = off; 3=on;

I would suggest setting the drive for voltage mode. It should behave mostly the same as velocity mode.

Todd, many thanks for your continued support!
As per (page 5 of 9 Hardware Settings) I plan to try DIP setting to 1=on & 2,3,4=off ie. voltage mode. I will start fresh, when tuning PID , heavy axes 1st.

many thanks!

Many thanks for all the help!

I have reached out to AMC, a knowledgeable engineer suggested the following based on the screenshot.

forum.linuxcnc.org/media/kunena/attachme...12/01yScreenshot.png

Blue line is encoder speed. "The linear line indicate constant speed and it is lagging behind your command. Based on this graph, the motor is giving you everything it has." ""You either need to slow down the acceleration and/or you need to increase the bus voltage.""

The bus voltage appears to be steady at 75vdc. Measured between (P2) lead 4 and 5. To "slow down acceleration" edit the .ini file? I just need to be clear in an approach.

many thanks!!