Hi,
just recently I fitted a new spindle (3.5kw(S1), 3.4Nm(S1), 40krpm max, 10krpm rated, HSK32 tool interface).

Have been using it for a while and going great guns. Just love the ATC feature.

Started having issues a couple of days ago where the machine would randomly disable, that is the MachEnabled output signal would go low and stop all movement, but Mach4, the GUI would carry
on.....despite the <Enabled> LED remaining light. There is nothing in the  History to suggest a cause or noise causing a glitch, nor have any of the servo alarms or limits been triggered???

I was first of the opinion that the issue was somehow related to the new spindle. I disabled all inputs like limits, servo alarms etc to eliminate any small noise impulse from triggering a Disable,
or rather a 'partial Disable' where the Machine_Enabled signal would go low but WITHOUT the <Enabled> LED following suit.

What I did find was that I had made a simple PMC script that allowed the spindle coolant pump to carry on for twenty seconds after the spindle stopped. Just one rung. It works fine.
It has been since then that I've had issues.

I removed the PMC (by deleting the PMC files) and that has solved the issue. No more intermittent 'partial machine Disables'.

I have a few questions:
1) How do you remove the PMC object from the file tree? All I could do is delete the PMC files from the Mach4Hobby/PMC directory, but Mach now complains that the 'PMC Object is missing'
I've tried to delete the object from the PMC_Objects in the profile file tree by deselecting the PMC file to no avail. How do you do it?

2) Is it possible that the execution of a PMC script could cause problems elsewhere? My machine runs on a dual core Atom single board PC, and I'm wondering if the PMC is somehow stealing
resources in such a manner to cause this random and unexplained partial Disable?

My machine hardly ever gets turned off, so I will literally be Enabled for months at a time, and I've never had an issue with it Disabling unexpectedly before, much less the machine disable
an NOT change the <Enabled> LED.

Craig

To disable or enable a PMC you need to do this under the screen settings when your in edit screen
Have a look at the attached image:


If the PMC is turning off something yes it could effect the machine. You need to make sure that it is not trying to turn anything off when your trying to use it... It's like having your wife help you and keeps locking you out of the house while your trying to work on the car. (maybe my wife is the only one that likes to lock me out because she forgets I am at the house doing stuff LOL) ..

The PMC is very powerful but it can make some odd errors!

Hi Brian,
thanks for the reply.

That is indeed exactly the way that I populated the 'PMC Objects' and also how I tried removing them.

It took ten or a dozen times before I stumbled on the correct keystrokes before I could select and retain a PMC object from the drop down list.
Then it took many tries before I stumbled on to the correct keystroke sequence to remove an object.

Not quite sure why I cannot select or deselect an object from the drop down list, but it did take repeated tries before I succeeded.

What is certainly true is that with a simple and functional one rung PMC object it caused a random fault with one output signal, in particular the Machine Enabled signal,
and when that screws up you can have some weird results! Since I've removed the PMC object things have gone back to normal.

As it turns out I was using the PMC to schedule the spindle circulation pump. The pump is very good, but rather drones. Thus I want it on only when I need it.

When the spindle turns on, and receives a signal from the BoB to that effect it turns the pump on......but for a few seconds after the pump turning on the flow detector has yet
to measure any flow, and this would normally be considered a fault. Thus I need a small delay such that the flow detector could reliably signal spindle coolant circulation before triggering a spindle alarm.
Also at spindle turn off I want the spindle coolant circulation pump to continue for twenty seconds or so, in part to ensure that the labyrinth seal air purge remains active (being commoned to the
spindle coolant circulation pump).

I have made a small PCB that handles the interlock, spindle fault, tool change air, taper blow air and monitors coolant flow, spindle temp and the tool detect switches. The PCB has a small 8bit micro so
it was really just a case of programming it properly to handle the pump scheduling/air purge scheduling. The PCB handles the spindle pretty much autonomously. seems like I have it working OK.

Craig