Re: [CAD_CAM_EDM_DRO] Re: Stepper Motor and Cable Shielding. Any tips?

eforum3001 wrote:

>
> How much more useful is an oscilloscope cf with logic analyser? I
> suppose the analyser can't tell when the pulse train is not "clean"?

When tracking down signal noise problems, a scope is a good deal
better, in most cases. One of the benefits of the LA is that it freezes
a snapshot of the event, and can often be programmed to actually
recognize something in the data stream (timing, relationship between
signals, etc.) that signals something has gone wrong. The cause of the
problem can then be found by searching backwards in time until you
find the signal that did it. This is possible because the analyzer records
continuously until the trigger event STOPS the recording, so you can
have a programmable amount of data retained from before the event.

> Hoping to hear about the experience of those who had found the
> analyser/scope, eg:
>
> "When the x-axis started to lose steps, I connected the analyser to
> the pulse generator, and found that .......... etc. etc.

I doubt that a logic analyzer is of great value in determining the cause
of lost steps, except in the case where you need to prove to the programmer
that there are abrupt fluctuations in pulse rate. It will do this job
superbly. If the stepper drivers are just being driven beyond their
speed/acceleration capability, then it won't be of great help, except
to record the exact pulse rate, and prove that accelerations in the
pulse train are gradual.

Jon