Set up using AMC AB15A100 drives, brushed DC motor Prototrak Plus with Encoders

Todd Zuercher, Many thanks. I have placed SW1-5 OFF, now both drives have red LEDs are on. I am keeping AMC in the loop & was agreed to try SW1-5=OFF. Soon I need to mount motors on machine so a load can be applied.

Don't forget, Linuxcnc only reads the ini file at start up time. So If you make changes to it while it is running, they won't take effect until you exit and restart Linuxcnc.

Good, So you do not currently have the motors mounted to the machine. That is wise for initial testing. You say you have a red led on the drive? What state is Linuxcnc in with the drive's red led on, running, e-stop, machine on? The red led may simply mean that the drive is inhibited, which would be the correct state for all situations except when Linuxcnc is in the machine on state, at which point I think the drive's led should turn green.

The red LEDs are on both drives, all the time. If you click F2 down, the red LED will flicker ever so slightly, before joint error out. IF sw1-5 is OFF.

Edit:
If SW1-5 is ON, just powered up, so F1 is up; Green LEDs, motors run slow with plenty of torque (if try to hold motor shaft); If all the same but F2 down, red LEDs, motors stop, but turn by hand and see DRO work; F2 up, green LEDs motors slow with torque if try to hold motor shaft.

Is there any motor movement? The joint following error is triggered by the difference between the commanded position and the feedback position read from the encoders. If that difference exceeds the amount set by FERROR= (following error limit at low speed) and MAX_FERROR= (following error limit at maximum velocity) The actual following error limit is linearly interpolated between those two values depending on the velocity of the joint. When the joint was enabled the motor should have at least turned the amount of the FERROR= before triggering the joint following error.

Possible reasons for the motor to immediately trigger this error would be if the commanded feed back direction was backward, either at the drive or Linuxcnc, or the polarity of the velocity reference is wrong.

Todd, Thanks!! I power up, (SW1-5=ON) F1 is down, both motors run real slow, green LEDs; F1 is up, motors still run the same slow speed, green LEDs; F2 is Down, motors stop, Red LEDs; F2 is up, motors run real slow, Green LEDs. This is how it appears to work, when the motors are not moving they turn free, this is also the same time red LEDs appear.