em806 Senssorless Stall Protection fault

[Clive S]

the problem seam to have come back and now the y axis trips out in the same place every time on various files.

Charlie You say various files above.

t’s a single motor, it happens on the sasme g code line anywhere on the machine it doesn’t appear to be macanical.

But here yo are saying on the same line of gcode,

Will try too tomorow it happens with both

Not sure what this means.

Is it just one axis that is tripping if so can you be a bit more specific as to what is actually going on.
As Neale has suggested does it trip doing fresh air cuts?

[charlieuk]

Ok so this morning I tried the same file as yesterday which I normal run at 150% and it still faults however run at only 100% it is ok. I have a friend here who knows a little more so we have swapped the two drives over to see if the problem changed drives however now doong a rapid move on the y axis just using the keyboard trips the same driver as before which is now on the z axis.

[charlieuk]

Charlie You say various files above.



But here yo are saying on the same line of gcode,

Not sure what this means.

Is it just one axis that is tripping if so can you be a bit more specific as to what is actually going on.
As Neale has suggested does it trip doing fresh air cuts?

The drive is giving the same sensorless stall protection fault on the same file each time if I change the file it faults again but at a different point in the file but is repeatable if you re start the file. The fault causes a external e stop on Mach 3.

Yes the driver trips doing air cuts

Many thanks

[charlieuk]

Here are the two motor tuninging numbers for y and z that use the same driver Then the x on the junco drive

[charlieuk]

This is two different files and the lines of g code it is stoping at doing air cuts just at a random location on the machine, the third picture is the cut I was doing yesterday when the problem first arose again

[m_c]

Did you re-tune the drives after swapping them?

[charlieuk]

No we didn’t


However we did re tune the drives after changing back to the original settings which did not make any difference.

After that I went back to playing with the motor tuning speeds and have reduced both y and z and it has now been running for a hour or so however it does not seam quite right as it looks like it has cut some corners or not done the tool path correctly.

How do you know how to set the speeds of each motor to get the most with out problems?

[Ger21]

Mach3 has a known issue with running at higher feedrate override settings. You're better off setting the feedrate higher in the g-code and dialing down the override. Turning it up to 150% and higher can cause issues.

[m_c]

How do you know how to set the speeds of each motor to get the most with out problems?

Keep increasing the settings until the motors start stalling, then reduce them to create a bit of a safety margin.

You have to find a compromise between acceleration and max velocity though. With less acceleration you can ultimately get the motors to spin faster without stalling, however if you're planning on doing things that involve lots of small moves, then sacrificing top speed for acceleration, will often result in faster machining times.