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Re: UCCNC startup G18

PostPosted: Sun Oct 29, 2017 2:50 pm
by ger21
- by me (and I think a lot of people) reset controls charge pump and charge pump controls the main power supply for the machine. I do not want to turn my power supply on for only some milliseconds!


Another good point.
It wouldn't affect my setup, as I use the charge pump with a safety relay. I use an external button to power the system. It relies on the charge pump signal being present, but the charge pump itself does not power the system.

Re: UCCNC startup G18

PostPosted: Mon Oct 30, 2017 7:38 am
by dezsoe
Robertspark wrote:Dezsoe, why are you toggling your power supply on and off under chargepump signal?
Why not use the enable pin on your drives, and an interlock on your VFD / spindle?

If you physically drop the power out to your stepper / servo drives + VFD they have no way to come to a controlled emergency stop using breaking as quick as is possible.

{I do take your point though about the xxmSec pulse of e-stop / reset clear, I'll take another look at your macroloop}

I don't know why but I'm reluctant to have a load of macroloops even though I know that they are constructed in such a way that they will just check a status and return and little delay will be induced by the loops.

I have small, desktop size machines. When I press e-stop I need everything to stop. By work conditions I only had to press e-stop 4-5 times in the last years, mostly to prevent tool and/or workpiece damage.
On the other side, sometimes I have UCCNC running even a whole day while writing macros or plugins, but it would worm my motors, so I only turn on power when I want to do something. I also have a macroloop with some on-screen parameters to auto-power-off after a given timeout. So, it became a good and safe practice for me to switch the motor power with the charge pump.
And one more reason is that in the past I had only a UC100 and didn't have free output to use enable. Now I have UC300 and UC400 also, but for compatibility I use the same pinout (for motion and probe) so I can change the controllers to run tests on any controller and any machine.