Prototrak Plus Retrofit with Mesa 7i77 & 5i25 cards

Many thanks, for all the great help, I have not been able to find the PWM (the round dials, in the link) dials, is there a "flip out/pull down" tab I'm missing or not finding? The "x" will move under "jog" on command with correct DRO direction (best news yet), and hopeful for complete success! "y" DRO works, only so far.


forum.linuxcnc.org/10-advanced-configura...ning-detailed-how-to

This is from tommylight, a well written "the best "how to" servo tuning ever" "" ===On the calibration window, you should set the ff1 to 0, add something like 0.00001 to the dead-band field, leave the rest as is, meaning everything at 0 except the P value. Do this for all the axis. Press OK and "save to file" on the "calibration" screen. ""

During this part of the process the "DEADBAND" was set to .00001 (as per direction) after using "save" then "test" it reads le-05, you can edit it and save, but will still come back. Is this an issue? It is only the "Tune 0" axes, the Tune 1 will not retain the .00001, it wants to stay at 0; same with Tune 2 tab. I'm working 1 axes at a time all the way thru.

Many, many thanks!!

Many thanks, to all that make this forum possible!

After confirming that the prior used AMC amps were not easily repairable I have a "new to me" set of AMC amps, I have swapped out servos to see if that helped the issue, but servos test ok.
The issue is that the servos will move under there own power when in "Test mode" , reverse/forward, change speed, both axes.
But when in "terminal" type in linuxcnc, as to run, the "x axes" will jog as per command with DRO correct direction, but "y axes" shows DRO ok, but will not jog, when servo should have "brake on (shaft locked)" it shows no braking at all, tried to increase "P", did not help or seen to change the braking part at all.

I tried another amp, jog works, DRO works. Attached are the .hal and .ini.

Edit: One issue is that the servo will jerk after jog is off, back and forth. These servos are off the machine, just using my foot to control the startup and the jerking at end. The jog speed is low 1.7" to 3"/min, seems to get better if you speed it up.

Many, many thanks to all!!

Many, many thanks tommylight for your valuable help and guidance!
I have tuned the servos several times, it is time to mount to the mill, with out the belt and tweak 1 more time before the belt is installed. At the end of jog, depending on how well the servo is restrained effects the scope display I believe. Below are links to the amp info, I am thinking certain settings should be the same on each axes, this explains parts of it, just can't get the ohm meter to read any resistance, to common ground.

The Advanced Motion Controls setup has a section that reads as follows: (This is from page 43 or pdf page 50/73) link: www.a-m-c.com/wp-content/uploads/support...ual_Analog_Panel.pdf

Test Points for Potentiometers After the potentiometer adjustments have been completed,
the resistance values can be measured for future adjustments or duplication on other servo
drives of the same part number. Test points for potentiometer wipers are provided and are
located at the foot of all four potentiometers. Resistance measurements are only to be used to
duplicate drive settings, since some potentiometers have other resistors in series or parallel.
Measure the resistance between the test point and the outer leg of the potentiometer or
between the test point and an appropriate ground. See the block diagram on the drive
datasheet to determine which ground should be used for each potentiometer.
Before taking potentiometer resistance measurements, make sure that
all potentiometers and DIP switches have been set to the desired
settings, and that all I/O and Feedback cables have been removed from
the drive, as these can affect resistance measurements.

I can see the "foot" or test point in question. What I am not completely shore of is the other end of ohm meter is placed to reference if it is not the common "ground"? The block diagram is here, pdf page 7/9: servosystems.com/pdf/amc/12a8.pdf
What needs checking is the Current Limit (2), this needs to be set the same on both axes.

many thanks for all the help!

Many thanks for all the help!

After tuning both axes, and watching the hal scope, I see changes when "P," is changed, not so noticeable are "FF1 or FF2". The one thing most noticeable is oscillation, especially at higher than 20"/min jog, especially at end or stop of jog, not so noticeable at slower feeds. This oscillation is something that I did not see when powered with old amps, should I re-think the (AMC) amp set-up? Could live with slower feed(up to 5"/min), will try to zero in on the preferred settings to best fit this vs. the full jog speed of 60"/min. The max "P" I used was 5000, this did not make servo vibrate, should I go higher? Tried the FF1 from .01 to .5; Deadband .00001; FF2 .001 or lower(ref to FF1).

Many thanks to all that make this forum possible, your suggestions warmly welcomed.

thanks andypugh!

Well there is Deadband that is tweaked as well as P and FF1 & FF2. The speed of the feed effects the out come the most it seems. What are you suggesting?

many thanks!!