Hi all, I have been reading through various THC posts and related documentation but haven’t yet found exact answer, or more likely my brain hasn’t caught onto which issue/solution best suited.
Yesterday I finally got around to making first cuts on CFPro.
It went well and no issues.
My THC voltage test yesterday before that cut was 128v
Today I came back out to make a second test cut, and had problems with piercing - sometimes on first, sometimes on second pierce with an error . " A plasma cutter misfire was detected by the LS-THC system"
So per that error message recommendation I increased pierce delay up from the default 0.5s - all the way to 1.0s before it was successful each time.
This made me wonder -what changed overnight ? So I re-ran the THC voltage test a few times, and now it shows around 54V instead of the 128v-ish from yesterday ?
What can cause this ?
The test cut is a simple 1.5" square with a 1" hole in middle
Material is 10ga (0.102") steel
The consumables are brand new - just these test cuts (consumables are from Everlast with my machine torch)
I am running it at 40A and 60ips
THC is connected internally to RAW voltage, banana plugs and PV out
Everlast PowerPlasma 50S
The cut quality is good when it cuts
Any ideas on what I should check ?
So weird the huge difference in THC voltage overnight…
Also - I forgot to mention - below is a picture of a pierce that did start, but not complete, hence the increase in pierce delay.
But on a few tests, I could not detect that it actually started an arc - just did its - touch-off, lift to pierce height, then error.
Ok - now I just got a Ground loop error instead - which I check at the USB connector on CF controller and looked ok.
Then I unplugged the laptop power from wall - and back to 129v
I do have plastic isolator between controller and frame.
I can’t explain the voltage issue, but how much use has the plasma machine seen? I was having issues with my 52i failing to arc and found that the air solenoid was the problem. I had to take the solenoid apart and stretch the spring inside. It’s been firing consistently since then
I had nearly the same scenario. It cut fine then all of a sudden same issue you’re having when I filled the water table. Unplugging the laptop was the solution. I tested for continuity between the table and usb and only saw it once. Have not been able to reproduce the problem. It is in fact black magic!
Not that much usage - and it worked flawlessly before hooking it up to the CF.
It is working fine, good voltage when laptop not plugged into AC,
however I have not figured out why it only works with a 1sec pierce delay,
anything less and no fire.
What is your ground clamp hooked to? Material or table?
I have experienced similar symptoms when I have forgotten to hook up the work clamp. Maybe a bad connection there somehow?