QTPlasmaC Crashing bug report

I know you suspect EMI noise, but are you sure the float switch isn't actually getting tripped? I have had the same problem in the past when cutting material that warped during cutting. It doesn't take a whole lot for the material to push the torch up and trip the float switch. I also saw it once when I was messing around with the tuning of the THC and had made it too slow.

How much travel is in your float switch? I would recommend actually watching the floating head/switch while it's cutting to make sure it's not actually moving/getting tripped. It seems everything happens 10x faster while actually cutting :laugh:

I will try to replicate your scenario this evening and see if it causes my QtPlasmaC to crash.

I rebooted my machine last night before coming in the house. I don't know if that has something to do with it, but now when the float switch gets tripped while cutting, it pauses the program as designed, and is no longer crashing. So I couldn't get a crash report.

Now I will play with the debounce and see if I can eliminate the float switch falsely tripping. I don't think it is getting pushed by the material because the THC isn't doing it's job. Not outside of possibilities, but I was looking pretty close last night at that and it didn't appear to be happening.

I've have had a chance to record in the terminal when the tool crashes. I saved the report on my other computer and don't have it available to post. But I know what it says. Basically an arc OK signal lost on initial arc is causing the tool to crash. You can duplicate this by removing your ground clamp and running a job. I had an issue with QTPlasmaC sampling for Arc OK before my hypertherm is giving the signal. I thought this issue was from the float switch getting triggered, but I was wrong.

I have the issue resolved by adding time to the arc ok debounce value. So I don't want to get into that. It is working great now. But the tool still has the bug of crashing if arc ok is lost.

Also I had a crash tonight in the middle of a long job when I hit pause. Luckily it was easy to recover. But non the less the tool crashed and shut down.

Thought I would log my findings if you want to try to duplicate them. Maybe it is just my build, and not a bug at all.

Need to see the crash report. It will show where things are going wrong in the software. Without that it’s very difficult to duplicate the issue let alone know we duplicated the same issue.

Help us help you

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.