(Solved) PlasmaC new config Z going up when probing

Clive wrote:

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.

Clive wrote:

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.

PCW wrote:

Something limiting the Z axis velocity or acceleration could cause this
Also something wrong with the plasma voltage reading could cause this issue (too much filtering for example)

What does the plasma voltage do during the cut?

#******************************************
[AXIS_Z]
# set to double the value in the corresponding joint
MAX_VELOCITY = 10.000
# set to double the value in the corresponding joint
MAX_ACCELERATION = 100.00
# shares the above two equally between the joint and the offset
OFFSET_AV_RATIO = 0.5
MIN_LIMIT = -3.875
MAX_LIMIT = 0.001

[JOINT_3]
TYPE = LINEAR
HOME = 0.0
FERROR = 0.5
MIN_FERROR = 0.05
MAX_VELOCITY = 5.000
MAX_ACCELERATION = 50.00
# The values below should be 25% larger than MAX_VELOCITY and MAX_ACCELERATION
# If using BACKLASH compensation STEPGEN_MAXACCEL should be 100% larger.
STEPGEN_MAXVEL = 6.250
STEPGEN_MAXACCEL = 100.00
P = 1000.0
I = 0.0
D = 0.0
FF0 = 0.0
FF1 = 1.0
FF2 = 0.0
BIAS = 0.0
DEADBAND = 0.0
MAX_OUTPUT = 0.0
# these are in nanoseconds
DIRSETUP   = 10000
DIRHOLD    = 10000
STEPLEN    = 5000
STEPSPACE  = 5000
STEP_SCALE = 5080
MIN_LIMIT = -3.875
MAX_LIMIT = 0.001
HOME_OFFSET = 0.050000
HOME_SEARCH_VEL = 0.416667
HOME_LATCH_VEL = 0.083333
HOME_FINAL_VEL = 0.083333
HOME_USE_INDEX = NO
HOME_IGNORE_LIMITS = YES
HOME_SEQUENCE = -1
#******************************************

rodw wrote:

That almost looks like the THC is not enabled when it hits the material. Can you check the THC light is coming on in Plasmac?
Can you tell us the THC delay you have set?

It does work and this was with default settings and probably a bit more onerous than your test.

The Z axis velocity and acceleration is what limits cutting corrugated iron because the torch must follow the sinusoidal profile of the iron.
I have a spreadsheet calculator somewhere. I think for my machine it was limited to about 4 m/sec cut speed (oops there we go again)