Is this QTPlasmac Expected behaviour - Cycle Start and Jog disabled.

During cutting the voltage is set at 130V and on screen it fluctuates between 124 to 131 during cutting at 3.5m/m .
That might be a good trigger point for the plots...

tommylight wrote:

During cutting the voltage is set at 130V and on screen it fluctuates between 124 to 131 during cutting at 3.5m/m .
That might be a good trigger point for the plots...

OK, I'll make some changes to the comp and push it to master branch tomorrow. The changes won't affect normal operation so it will be safe for everyone to use.

Tom, I managed to cobble something together and have pushed it.

There are three additional pins:this is an input, you can set this so that if the arc voltage is lower than this while THC is active then the machine will pause and give an error message similar to this:



The next two you may not need:This is an output that shows the target arc voltage for THC.


This is an input that defaults to 6. You can change the number of samples needed to set the target voltage for THC.

Thanks, will give it a try after routing the network line to the new shop, all metal cladding so wifi does not work from the other shop.

tommylight wrote:

Thanks, will give it a try after routing the network line to the new shop, all metal cladding so wifi does not work from the other shop.

There is always something...

rodw wrote:

Tommy, I seem to remember you always set your voltage manually. Have you ever tried auto sampling voltage? What if your set point of 130 volts is wrong so Plasmac starts off on the wrong foot?

Try using halscope with the THC disabled to see what the voltage settles to naturally to set your desired voltage.

If the target was 130 and the arc voltage was heading down to around 80 then it should have raised the z axis, not lowered it.

It sure is weird ...

rodw wrote:

Tommy, I seem to remember you always set your voltage manually. Have you ever tried auto sampling voltage?

Yes, several times on all machines, it just settles to low, usually 96 to 102V so the torch remains at under 1mm from the material. All 3 machines have a working voltage of 115 to 132V.
I am pretty sure i can manage that with some tuning to go above, but usually when i am near the machines i am cutting something, so no time to play with settings. Either way i have to play with cut feeds and current and other stuff as i change plasma sources often.
Also pretty sure this issue happened also while using auto volts, but do not quote me on that.