Anilam Crusader M 3 Axis Mill

Hello,

I am going to upgrade my Anilam Crusader M 3-axis mill and just needed some advice. The hardware is all in good shape but the control is starting to act up and it is time to upgrade.

I am going to keep the 3- 140v DC SEM servos along with the power supply and Servo Dynamics 1525 servo drives. I will keep the tachs and run the drives in velocity mode. I will also re-use the E-stop and limit switches.

I planned on using the 3- linear scales and read heads already on the mill to close the loop. They are 5v TTL quadrature scales.

I was going to use the Mesa 7i76 along with the 5i25 card. I also plan on adding an encoder to the z-axis for rigid tapping and also a VFD for spindle control.

I see the 7i76 has 6 encoder inputs and appears to accept 5v TTL signals.

My only concern is what do I have to do in Linuxcnc to get the drives to run in velocity mode with the tachs and also use the scales to close the loop.

Before I start buying cards I want to make sure what I am trying to do is even possible with the Mesa cards.

Thank You in advance for any help you can give me.

-Steve

For analog drives you would use a 7I77, not a 7I76

Normally if you have tachometers, the drives will already
be setup in velocity mode.

Decent operating with linear scales as the feedback does
require very low backlash.

The scales I have on the machine now are 5v TTL quadrature. Will they work as they are, even though they are TTL?

The drives and servos work fine on the machine, although when they are stationary they dither .0005" back and forth sometimes looking for position. I spoke to an engineer at Anilam when I got the machine and he said that was normal for the Anilam Crusader M to do that.

Also, I would really like to replace the drives why I have it torn apart. I have looked everywhere for compatible drives and have come up short. I have looked for AMC 25A20 and Copley 423's which will work with the power supply and servos I have now but I cannot find them at a reasonable price. If anyone has any suggestions on a drive to use that will run the 140v DC SEM servos with the tachs I would appreciate it.

Also, thank you for correcting me on the 7i77.

Thank you all for the help.

-Steve

5V TTL quadrature scales will work.
Any particular reason for you to change the drives?

I mainly wanted to change out the drives because of the loud whine they make. I think it is because the carrier frequency is low enough it can be heard. I can live with the noise if you guys think that is best.

Thanks for the help!!!

-Steve