[Igloomason]

I have a external closed-loop spindle speed controller (SuperPID) that, annoyingly, only runs from an active low pin. This is fine when Mach3 is running because I can just configure the run pin to active low. However, under certain conditions the spindle will dangerously start running unintended (eg. the machine is on and while the computer is being booted up).

My solution is to have the speed controller powered up (not just activated) from a HIGH pin as instructed from Mach 3. That way, unless M3 is open and running, my speed controller won't be powered up and a HIGH or LOW run pin will be inconsequential. How would I configure M3 to do this? I've never used a charge pump, is this the type of application in which I would?

[dazp1976]

Could do with knowing what control board you are using.
I would look into small isolator modules to control your M3/M4.

If you are using one of those 5 axis boards and the on-board relay, I had trouble with it.
If you have outputs (from Mach input output pages) configured to m3/m4 AND have spindle dir assigned in motor pages, the 2 will conflict.
Dir should be 0. Outputs#1-6 in Mach pages configured to bob pin, those outputs configured to m3/m4.

[Igloomason]

I'm using the C1 PP Interface Card Rev5 - CNC4PC. There are no mechanical relays on board. I have OUTPUT #1 configured to RUN my speed controller (active low) when a spindle command is called. I have no DIR pin selected for spindle in motors tab.

My understanding is that M3 can generate a charge pump signal on a designated pin. I'm wondering if I can use this pin to actually power my speed controller thus avoiding an additional piece of hardware.

[ger21]

the spindle will dangerously start running unintended (eg. the machine is on and while the computer is being booted up)

You should never have the machine powered up without the computer.
The proper way to use the charge pump, is for the charge pump to not allow you to power up the machine until Mach3 is in control.

[Jim Dawson]

Why is there no hard E-stop in your system? Every machine needs a big red button, push to turn off, pull to turn on.

[faultmarten]

The charge pump should not enable the machine to be powered up until Mach3 is in control of the situation. This is the correct approach to use the charge pump.

dumb ways to die