(Solved) PlasmaC new config Z going up when probing

snowgoer540 wrote:

Clive wrote:

We had to change the THC delay to 0.3 secs

FWIW, in the past they've told me here that a similar time wasn't long enough for the voltage to settle down, and highly recommended I use the default which is 1.5 seconds (I believe).

I think 1.5 seconds comes from me. It comes from lot of halscope plots I did with my Everlast on 2mm and 8mm mild steel. The thicker material made a bit of difference but it was a bit slower settling to cut volts. I reviewed this again when I bought my Thermal Dynamics with more plots but I did not see anything that made me want to change that setting, even on 16mm. I will eventually do some more tests becasue I think that machine acceleration is a factor here. I suspect now my machine can accelerate at 5 m/s^2, that that will significantly shorten this delay period.

Plasma cutters are constant current devices so the inverter changes the voltage to maintain that constant current.

I would suggest you do some tests with halscope to come up with your own delay becasue I think your acceleration settings will influence this delay. As we are all learning as we do this, I think this probably should be part of your initial tuning process.

Re the question about sane values for volts per mm, you should know by now the answer is in the plasma primer! 10 volts per mm has long been accepted as the average but on my Everlast I did some regression analysis and concluded that it was 7.53 volts per mm. IN practice, this number does not need to be precise because the PID loop will converge on the answer.

Yes its strange the machine above would not work with P10 and delay 1.5 just changing these two things made the machine fly we have just cutout a big control panel using Hypertherms cut parameters in 3mm alli at 7.5M/min without any issues.

tommylight wrote:

Clive wrote:

Yes its strange the machine above would not work with P10 and delay 1.5 just changing these two things made the machine fly we have just cutout a big control panel using Hypertherms cut parameters in 3mm alli at 7.5M/min without any issues.

If there are no pictures or video, it did not happen ! I was told this same thing by a member here not long ago.

Ok I will put them both together. Doubting Thomas.


.

I’m with Phill, what did you mean by P10?

Ok I have had a few sherbets so please excuse me.

P10 is the pid loop whatever in the ini file and the machine in question that I had to help set up was 40 miles away so done with phone and Dropbox. we had to increase the P10 TO 2O to get it to work.