Centroid Community CNC Support Forum

I purchased the ajax mpg to work with my mach 3. It only took minutes to install and is working great with one exception.
If I turn the mpg to fast the buffer in the mpu11 continues to feed the drives after I stop turning.
This can be a very dangerous situation. Can I change a setting that will stop this?

Hello,

Unfortunately, I don't have an easy answer for you.

This is the classic MPG dilemma:

Many operators want the control to respond to the MPG in a manner that commands a move that is an exact representation of the number of pulses generated by the hand wheel regardless of when it stops turning. This can lead to "wind up/buffering" of the mpg counts and can cause movement to continue for quite a while after the hand wheel is stopped.

The "other side" wants a move that stops as soon as the handwheel is stopped.

We kind of straddle the fence on this - we do stop commanding motion as soon as the handwheel stops but there will be some motion as the axis is smoothly decelerated to a stop. The amount of motion is dictated by the accel rates defined for your axes in the Ajax plugin config. If you need it to stop faster, shorten the accel times - but be aware that will affect all moves for a particular axis and not just MPG moves