I am deep into the design of the controller for my mill, and I have discovered that the ClearPath servos I will be using have a data channel on them that provides a PWM signal that tells you how hard the motor is working.

This suggests that I can do per-axis load displays, potentially with alarms and other features - some sort of sliding "progress gauge" with an associated numeric value would be cool.

Anybody done something similar?

Hi,
Mach4 is a buffered motion control solution so you cannot rely on the feedback data from the servo to be realtime.

For example the ESS has a default cycle rate of 40Hz. Thus there could be a delay of up to 25ms between the servo uploading
data until the time Mach4 gets it. You can increase this rate, I've heard of some people with quick PCs running at 200Hz and thus the delay
would come down to 5ms, but even a 5ms delay is not realtime if you want an alarm type instantaneous response.

In the other direction the ESS has a default motion buffer length of 180ms. Thus any movement instruction could be delayed by up to
180ms before the servo actually does something. Again I have heard that some people with quick PCs have reduced the motion buffer to 30ms
but even 30ms is not realtime.

Provided you are aware of the potential delays in an 'around the loop' communication and that delay does not compromise your intended
purpose....then yes monitoring the output would be possible.

Craig

why you need this?
if to stop on emergency just use the input servo error
if to limit the power you can do all by the servo pack,you can also combine torke control in some cases
i use to read data from driver only in homing because i use absolute encoder
but i didnt try read it while machine run

> Provided you are aware of the potential delays in an 'around the loop' communication and that delay does not compromise your intended
purpose....then yes monitoring the output would be possible.

Ack.

I think the worst-case scenario - an overload during rapids, call it 200in/min, 5ms = 0.017" movement - is a fast enough flash-to-bang to still be useful. And really, it is less about the alarm at 100% than it is about monitoring effort during a cut. If the axis is at 20% utilization, then maybe the cut can be pushed harder.

Is there a sliding-scale 0-100 screen widget?

Is there a reference that shows all the screen widgets availible?

There is an 'angular meter' widget that will probably do what you want. In the 'Docs' folder there is a file:
Mach4 Screen Editor V1.0.pdf
This is a must read for anyone wishing to customize their screen set.  Unfortunately it has not been updated with all of the latest changes.

HTH

RT

Is there a sliding-scale 0-100 screen widget?

Yes, it can be customised as you need with colours/segments/3D effect etc.  It is the 'gauge control' next to the MDI control in the screen editor