QTPlasmaC Crashing bug report

Nick7251 wrote:

........ You can duplicate this by removing your ground clamp and running a job. ,.........

my 2 pence / 2 cents....

when you remove the plasma clamp (it's actually + / positive with respect to the torch, the torch is - / negative polarity)
you are forcing the torch to use its High Frequency circuit to maintain the plasma arc ..... hence in my opinion you have an electrical noise problem which is causing a spike and upsetting Comms...... are you using a shared earth and zero volt connection?


you use of the word "ground" has me worried as many don't understand what ground, earth, and zero volt are and that there is a difference

robertspark wrote:

Nick7251 wrote:

........ You can duplicate this by removing your ground clamp and running a job. ,.........

my 2 pence / 2 cents....

when you remove the plasma clamp (it's actually + / positive with respect to the torch, the torch is - / negative polarity)
you are forcing the torch to use its High Frequency circuit to maintain the plasma arc ..... hence in my opinion you have an electrical noise problem which is causing a spike and upsetting Comms...... are you using a shared earth and zero volt connection?


you use of the word "ground" has me worried as many don't understand what ground, earth, and zero volt are and that there is a difference

Don't worry, it will all be okay.

I know that it is actually the + lead, but a lot of people still call it the ground clamp as they bring the term from welding. Even though that is wrong, most still understand. But when talking about an EMI issue it is important to clarify, so thanks for giving me the opportunity to clarify.

I used to have the + clamp connected to my table star ground but I was getting the arc lost error a lot. So I now put the clamp right on my material.

My star ground has a connection to an 8' earth rod. Each stepper goes to the star ground as well as my control box chassis.

I agree with you that it is possibly an EMI issue, but the bug in my opinion is that the software is crashing instead of pausing. PlasmaC would pause and give me a chance to resume my cut. QTPlasmaC crashes and therefore i have no good chance to resume the cut.

I will post the terminal output sometime today.

Thanks all.

Here is one of the terminal outputs when it crashed.

interesting, I am wondering if someone could remove the arcOK signal from their setup during a cut (pulling a wire) to replicate?

To me, this appears to be a software error because:
1. Plasmac appears to catch the probe switch changing and prints a message about pausing
2. The error on termination appears to be coming from QTvcp (outside of plasmac)
3. The log shows normal termination. This is reasonable if the GUI (QTvcp) is closed for some reason.

The only way I could think of that would place responsibility of this with QTPlasmac would be if somehow it was returning an invalid value to QTvcp which told it to shut down.

I think this should be raised in the QTvcp section or in the issues report on GIT.

Nick7251 are you running the current master branch? {just checking the obvious regarding an lookis like you are running xxxx 3713xxxx from 2021-03-25}

do you want to try upgrading to the latest master (just in case its a cleared issue due to something changing or being removed etc)

Next.... check for .... electrical noise spike.... (double, tripple check your wiring, do you have a schematic, as rough as they come is better than nothing to at least review)

Thanks all for your input, but please refrain from trying to fix the fact I am losing pilot arc. I have already resolved that problem. I am just reporting that when I was having the problem, instead of the software pausing like it should or like it does when I was on PlasmaC, it would throw an error, then any button I could click would close the software.



This time when I clicked show report, it actually showed the report instead of crashing. I guess I got lucky.
The error report says the following:
Then if I click abort, or retry LinuxCNC would close.

Also as far as being on the latest build. I am no linux guru, but I am pretty sure I am the most up to date I can be. I have seen this problem on builds starting with 1.0 to current. I just upgraded before duplicating the error for you all again tonight. Says I am on xxxx 3764 xxxxx QTPlasmaC v 1.09


I pretty much update anytime Linux tells me to.

Do you have a Torch Pulse button set in the .ini file as a user button?