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I think you have a wiring fault. All the 105 does is close an internal relay when a valid arc is established. you provide the voltage to that relay and read the output when it opens and closes.I would confirm behaviour with a multii meter before going further.

We can't help until you provide full details of your THC, the way you have integrated with linuxcnc and the connections you have made.

Most people  use a Mesa Ethernet card and Mesa THCAD and not use an external THC.

Please don't duplicate your replies.

Thank you Rod for your advice.

I'm testing when I have the chance. I can put the 1/32 divider frequency. I'm used to THCAD300 and always put on 1/128.

The sticker value for my THCAD2 is: FSV - 899.4 kHz | 0V - 96.8 kHz

The initial value for the offset was about 700 but I've noticed that when the Power Source is Down (No Power) the arc voltage is 0V. When I turn On the arc voltage goes to 12V.

Checked the encoder velocity pin with the value of 900. Put 900 in the offset. Arc voltage has 0V and got decent results.

Made some tests today. When I make the first pierce the arc voltage, in the first moments turn in -73 and then goes back to normal value.
After that the pierces (should be a higher value than the Cut Volts on material) seems normal to me.

Talked with the supplier of the plasma source and he refers HF equipment and to check the grounding. Reinforced the grounding connections which has a good grounding less than 0.3 Ohm.

Now you have a THCAD 2 you can do more tests.
But normally, you would set the THCAD to use 1/32 frequency. This would alter your offsets etc accordingly. Make that change
Assuming a 10 volt range, apply a 9 volt battery to the THCAD  HV input. The flashing light should change frequency. Does it?
the voltage should be about  90% of your full volt range. Is it?
What are the calibration frequencies for your THCAD on the sticker?
Read the encoder velocity at 0 volt at rest and at 9 volts.
What are these readings?

If you read the QTplasmac docs, there is a link to a calculator to determine your settings.

I'm using the calculator from the PNCconf. 

SOS UPDATE:
Changed the THC to THCAD2 and change for a divided arc
Put the THCAD2 outside the plasma source in a plastic box.
Shielded only on THCAD2, in new cables. 

Made the changes that you recommend:
   

Results:
This worked a week, but it happens again. The arc voltage is on -45.

I can take more pictures, make video. If anyone can help.
 

You still did not answer what the Z motion range was

Anyway say its 50 mm and using the /32 tap that's
a encoder scale of ~415

When tuning you need to loosen the following error limits
and have some reasonable output scale value:TYPE = LINEAR
HOME = 0.0
FERROR = 50
MIN_FERROR = 50
MAX_VELOCITY = 25.0
MAX_ACCELERATION = 750.0
P = 50.0
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
ENCODER_SCALE = 415 # estimate with THCAD /32 and 50 mm full motion
OUTPUT_SCALE = 10
OUTPUT_MIN_LIMIT = -10.0
OUTPUT_MAX_LIMIT = 10.0
#MIN_LIMIT = -100.0
#MAX_LIMIT = 0.01
MIN_LIMIT = -15000.0 # these should be some reasonable numbers one you get the encoder scale correct
MAX_LIMIT = 15000.0
HOME_OFFSET = 0.0
loadrt offset
addf offset.0.update-feedback servo-thread
addf offset.0.update-output servo-thread

setp offset.0.offset -5671.078   # for /32net z-pos-fb_with_offset <= hm2_7i96s.0.encoder.00.velocity #New Line
net z-pos-fb_with_offset => offset.0.in
net z-pos-fb <= offset.0.out
net z-pos-fb => joint.1.motor-pos-fb
net z-index-enable joint.1.index-enable <=> hm2_7i96s.0.encoder.00.index-enable
net z-pos-rawcounts <= hm2_7i96s.0.encoder.00.rawcounts



 

What is the Z motion range for 0 to 10V out from your sensor?

Response:
ranger 10364.831 hm2_7i96s.00.enconder.00.velocity
ranger 621866.8 hm2_7i96s.00.velocity-rpm
I am testing with jump 64 on the THCAD2 board.

Simulations with other jumpers:

advanced hydraulic cylinder THCAD2 jump128

1416.431 hm2_7i96s.00.enconder.00.velocity
84985.84 hm2_7i96s.00.velocity-rpm

 

recessed hydraulic cylinder THCAD2 jump128

6616.257 hm2_7i96s.00.enconder.00.velocity
396875.4 hm2_7i96s.00.velocity-rpm

 

advanced hydraulic cylinder THCAD2 jump64

2868.069 hm2_7i96s.00.enconder.00.velocity
172084.1 hm2_7i96s.00.velocity-rpm

 

recessed hydraulic cylinder THCAD2 jump64

13232.51 hm2_7i96s.00.enconder.00.velocity
793950.9 hm2_7i96s.00.velocity-rpm

 

advanced hydraulic cylinder THCAD2 jump32

5671.078 hm2_7i96s.00.enconder.00.velocity
340264.7 hm2_7i96s.00.velocity-rpm

 

recessed hydraulic cylinder THCAD2 jump32

26449.64 hm2_7i96s.00.enconder.00.velocity
1586979 hm2_7i96s.00.velocity-rpm

 

I put the value 800 in the scale encoder, but it continues to display a calculation error message on the axis, but the axis moves a little, below is the video showing the result



Regarding another question, sorry for my lack of knowledge, do you have any example of how to: feed the encoder velocity signal through LinuxCNCs
offset component to remove the offset at 0V ?





















 

One thing I see is that the Z encoder scale is off by orders of magnitude.
If you are using the ~100 to 900 KHz range of the THCAD2, I would expect
and encoder scale to be roughly 800,000 / Z_motion_range.

What is the Z motion range for 0 to 10V out from your sensor?

It addition the scale may need to be negative. This is the first thing to get setup correctly

Also as I mentioned, you may need to feed the encoder velocity signal through LinuxCNCs
offset component to remove the offset at 0V
 

I can't find a suitable configuration so that the analog output can control the correct movement of the punching machine's piston. How do I solve this?Summary of what I'm trying to control:The piston that hits the punches is hydraulic, but it has an actuator that controls its descent and ascent by applying analog voltage of -10 volts and +10 volts, where +10 volts goes up and -10 volts goes down. However, unlike a motor, when there is no voltage at all, the piston descends gradually. To keep it high, a voltage above 2 volts positive will always be necessary.Hardware information: the sensor that detects the movement of the piston hitting the punches is magnetic and provides an analog output voltage, being 0 volts when it descends completely and 8 volts when it rises completely. This position voltage is connected to the THCAD2 electronic board that converts it into frequency. This frequency is used in channel 0 of the 7i77 electronic board's encoder, which is configured asThis reading is being shown on the display after the following modificationI'm worried that the problem is becausewas disconnected since it is being used to report the position, will the 7i77 electronic board work without net z-vel-fb?

Below is information that may helpWhen I manually jog the Z axis to 1mm or 5mm, it makes no difference in the actual movement of the piston, it always moves the same and the Z axis calculation error appearsWhen I manually jog the Z axis to 1mm

  When I manually jog the Z axis to 5mm  Piston hitting the punches in the zero position

  Piston hitting the punches in the position after a 1mm jog

 
 Piston hitting the punches in the position after a 5mm jog  I have been working on this machine retrofit for over 2 years, unfortunately here in Brazil I have not found qualified labor to perform this service. If I cannot resolve this step I will have to give up on LinuxCNC. I am willing to pay if someone resolves this situation. Even so, I thank all the contributions from the Forum and Mr. Peter.

Try this:

# ---Encoder feedback signals/setup---

#setp hm2_7i96s.0.encoder.00.counter-mode 0 #Default PNCConf Wizard
setp hm2_7i96s.0.encoder.00.counter-mode 1 #change to accept signal from THCAD2 board as Z axis feedback
#setp hm2_7i96s.0.encoder.00.filter 1 #Default PNCConf Wizard
setp hm2_7i96s.0.encoder.00.filter 0
setp hm2_7i96s.0.encoder.00.index-invert 0
setp hm2_7i96s.0.encoder.00.index-mask 0
setp hm2_7i96s.0.encoder.00.index-mask-invert 0
setp hm2_7i96s.0.encoder.00.scale [JOINT_1]ENCODER_SCALE

net z-pos-fb <= hm2_7i96s.0.encoder.00.velocity

#net z-vel-fb <= hm2_7i96s.0.encoder.00.velocity
net z-pos-fb => joint.1.motor-pos-fb
net z-index-enable joint.1.index-enable <=> hm2_7i96s.0.encoder.00.index-enable
net z-pos-rawcounts <= hm2_7i96s.0.encoder.00.rawcounts

Good afternoon, dear friends.

Please, how should I make the connections in the HAL file so that the 7i77 electronic board accepts the frequency generated by the THCAD2 electronic board as feedback from the Z axis?

Below is the basic code generated by PNCConf from LinuxCNC:

Note:

The TCHAD2 electronic board receives the analog voltage from the Z-axis movement which is a magnetic sensor with repeatability accuracy of 10µm (MICRA, micron or micron), with a recordable speed of 10m/s (meters per second) and IP67 classification (dust protection and water and oil resistance).
This sensor provides 0 volts at the output when the Z axis is lowered and 8 volts at the output when the Z axis is raised. The TCHAD2 electronic board converts this voltage into a frequency of 100kHz to 1Mhz (according to the chosen jumper). Then the 7i77 electronic board receives this frequency on encoder channel 0. It displays the position results counting to infinity, with only velocity being usable as position, with the low Z axis having a low frequency and the high Z axis having a high frequency.
Please, any basic example helps or suggestions. I appreciate your collaboration. Attached is a video showing how the values ​​from the TCHAD2 electronic board are being received by LinuxCNC.

*MICRA: The symbol (µm) and correspond to the microscopic unit of measurement, where 1 micron is the same as dividing 1 millimeter by 1000


 

Hello everyone, I'm back, happy 2025 to all. Please, I need help to return to the retrofit process of a punching machine.
I have the hardware configuration 7i96s + 7i77 + 7i84d and THCAD2
I need to make the 7i77 board work to drive the Z axis with feedback from the THCAD2. To get a basic code example, I used linuxCNC's PNCConf to generate a basic code example.

The basic code generated was:

# ---PWM Generator signals/setup---

setp hm2_7i96s.0.7i77.0.0.analogout0-scalemax [JOINT_1]OUTPUT_SCALE
setp hm2_7i96s.0.7i77.0.0.analogout0-minlim [JOINT_1]OUTPUT_MIN_LIMIT
setp hm2_7i96s.0.7i77.0.0.analogout0-maxlim [JOINT_1]OUTPUT_MAX_LIMIT

net z-output => hm2_7i96s.0.7i77.0.0.analogout0
net z-pos-cmd <= joint.1.motor-pos-cmd
net z-enable <= joint.1.amp-enable-out

# ---Encoder feedback signals/setup---

setp hm2_7i96s.0.encoder.00.counter-mode 0
setp hm2_7i96s.0.encoder.00.filter 1
setp hm2_7i96s.0.encoder.00.index-invert 0
setp hm2_7i96s.0.encoder.00.index-mask 0
setp hm2_7i96s.0.encoder.00.index-mask-invert 0
setp hm2_7i96s.0.encoder.00.scale [JOINT_1]ENCODER_SCALE

net z-pos-fb <= hm2_7i96s.0.encoder.00.position
net z-vel-fb <= hm2_7i96s.0.encoder.00.velocity
net z-pos-fb => joint.1.motor-pos-fb
net z-index-enable joint.1.index-enable <=> hm2_7i96s.0.encoder.00.index-enable
net z-pos-rawcounts <= hm2_7i96s.0.encoder.00.rawcounts

# ---setup home / limit switch signals---

net z-home-sw => joint.1.home-sw-in
net z-neg-limit => joint.1.neg-lim-sw-in
net z-pos-limit => joint.1.pos-lim-sw-in

But when trying to apply this example the error appears:

hm2_7i96s.0.7i77.0.0.analogout0-scalemax not found

The board The 7i77 electronics have all the necessary voltages, all the yellow LEDs are on and the green one too.

I have already managed to control the output and input through the classicladder, but unfortunately I am not having success in controlling the Z axis.

The HAL configuration is

loadrt hm2_eth board_ip="10.10.10.10" config="num_encoders=8 num_pwmgens=1 num_stepgens=5 sserial_port_0=3000"

Note: the number 3 in sserial_port_0 was necessary to recognize the 7i84d

How do I solve the error problem: hm2_7i96s.0.7i77.0.0.analogout0-scalemax not found?

I appreciate any suggestions or basic examples for configuring the 7i77

vre wrote:

Where can i buy both cards and thcad2 from europe in good prices ?

www.eusurplus.com
www.welectron.com/navi.php?k=324

Hello.
7i48 has 6 channels by muxing has this any limitation compared to 7i37 ?
Where can i buy both cards and thcad2 from europe in good prices ?

I am attempting to connect a THCAD 10 to a Everlast supercut 50. It does not have any CNC connections. It is a HF machine and I was told I needed to connect to the DC plasma supply before the HF coil. I am looking for pictures or a wiring diagram for this machine. I can not find anything. 

Thank you for the info