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Thank you Master PCW
I used (pncconf) to get some sample code to apply to the project. The code looked like this:

 

The frequency reading is appearing on the panel, but when trying to move it, this Z-axis movement calculation error appears:

 

Please, how should I proceed? What alternative and configuration for this?

 

Thank you, Master PCW
In the factory, the Z axis is driven by the 7i77 board connected to 7i96s.

It works with a positive voltage of 10 V, the punch goes up, and with a negative voltage of 10 V, it goes down.

I am in my laboratory, hundreds of kilometers away from the factory. Unfortunately, I do not yet have two 7i77s to do all the simulations here. But I do have two 7i96s to do the simulations here in the laboratory, while the other one has already been installed on the customer's machine. However, before I travel again, I need to have the programming ready to apply it to the machine.

I have been working on this for a long time. You advised me to use THCAD2 to receive the signal from the magnetic ruler.

The big challenge with this machine is that the Z axis is a hydraulic cylinder that hits the punch and pierces the metal sheet, but this movement has to be done with millimeter precision. If it exceeds the limit, it pulls and deforms the metal sheet. I think your idea of ​​using THCAD2 is great, because it has some similarities in the way the machine works, because the purpose of THCAD2 is to control the height of the plasma torch and in my case it is to control how far the punch can reach the metal sheet. However, I am new and inexperienced in configuring Hal to connect this and the LinuxCNC system understands that the speed of the frequency is the displacement of the Z axis, for example at 100KHZ the cylinder advanced all the way and at 1MHZ the cylinder returned all the way. Because the future interest is that with the G code, I can determine the depth that can reach the metal sheet. I will check your recommendations, but if you can give me some examples, I would be very grateful.

You would use the encoder velocity as the joint feedback source for the joint used for the Z Axis

Basically, if you make a configuration (using pncconf or MesaCT) with Z being a
normal step/dir axis, you would replace the feedback coming from the stepgen
with the encoder velocity. What drives the Z axis?

Note that you need to scale the encoder velocity so it reads in machine units.
In addition, you will likely need to offset the reading
(perhaps using the scale or offset components)

The encoder scale will probably be a large negative
number, I can give you the math for this later. just stepping out
the door...

I am retrofitting a machine, where I need to control the precise movement of the Z axis, I am using the feedback from the THCAD2 electronic board to transform the signal from the analog ruler from 0 to 10 v into frequency, the frequency is being read by the 7i96s board, the speed information hm2_7i96s.0.encoder.00.velocity appears. How do I configure the connection in the HAL file to recognize this signal as a Z axis position encoder? Please, if you have any examples, I appreciate it.

Before applying it to the real machine, I am performing some simulations in the laboratory. Below are the examples

In this image, we have a stepper motor connected to the shaft with a potentiometer that provides a voltage of 0 to 10 volts to simulate what will happen in the machine.

 

In this image, we have a THCAD2 electronic board that receives 0 to 10v from the potentiometer and converts it into a frequency of 100 to 1000 KHZ

 


In this image, we have a 7i96s electronic board that receives only one signal A in ENCA+ and ENCA+ from 100 to 1000KHZ

 


It seems to me that only the hm2_7i96s.0.encoder.00.velocity signal is usable to inform the position.  Because the other signs are always counting and adding infinitely regardless of the movements.

 


I didn't find any example on the internet to apply this hm2_7i96s.0.encoder.00.velocity signal in Z position return position setting, please, can someone help me with example?

 

explanation video translated by artificial intelligence, sorry if there is any misunderstanding
https://youtu.be/5GN0cps-YLc

Doesnt QtplasmaC have the option to read voltage for the arc ok? It reads the voltage from the THCAD - 10 for the THC

I am building a CNC plasma table and I am going to use QtplasmaC. I am trying to find out the correct pin out for Torch on/off and Arc OK. I am using the Mesa 7i96S board with a THCAD - 10. I have attached the wiring diagram I am using but it is for a plasma cutter with external connectors. The plasma cutter I am using is older and does not have any of those. 

 

fmj435 wrote:

I have my machine running and everything with it seems to be running well. The one problem I have is the tips on the torch keep getting ruined and then the plasma arc seems to come out at different angles. I had thought maybe it was water in the air lines but I'm pretty confident that I have dried the air and it still happens. A 10 minute cut with a couple dozen pierces and I need to replace the cup. When the tip is new it cuts very straight and cleanly.

I have a 1.2 tip in the everlast 82i with it set to 45 amps and 80 IPM for 10 gauge steel. I have tried increasing the voltage more to the max rating for the tip but that didn't seem to change anything. I run the torch around .06 off the material with it on auto volts and it seems to keep that height pretty well with the THC. Wondering what I should focus on to get it tuned in. Is there anything out there in the way of a tuning guide for the THCAD? Thanks for any help.
 

I also have an 82i.  I have found that the stock Everlast torch is junk -- I also had the problem of consumables not lasting very long.  I switched over to two torches that are now my "go-to" torches -- they are the PE85C (shielded) and IPTM80 (non-shielded) from PowerEdge Cutter.  Consumables are a bit more expensive, but they last far longer than with the Everlast stock torch -- and if you get the retrofit kit, they have the advantage of being interchangeable; just mount the barrel on your Z-axis & screw in whichever torch you want to use.

Consumable life improved dramatically, even at 80-amps.  I run my torch at 6mm pierce height & 3.2mm cut height @ 100 volts on 1/2" mild steel plate with 1.2mm or 1.3mm tips. Speed is 450mm/ min.

Links to torches:

IPTM80:  IPTM80 Torch
PE85C:  PE85C
 

tommylight post=311679 userid=17274I do need one or two of THCAD, but shipping will cost at least 3 times the price!
Just for kicks, ask how much would it cost to ship to Kosovo, Eastern Europe.
You should really be sitting for the answer, and having a cold beverage in hand helps, a lot!

sitting down? i should have been laying down! it IS more than the cost of the item! by a LOT! one figure said $185 for just the transportation cost, without the export fees!

PCW wrote:

My guess is it might be the lack of debouncing on critical inputs.

The dbounce components are loaded but the raw parallel port signals
are routed to Plasmac and the dbounce component inputs, but the signal
paths should be:

parallel port pin --> dbouncex.in --> dbouncex.out --> Plasmac

That is you have for example:

net plasmac:float-switch <= parport.0.pin-12-in-not
net plasmac:float-switch   => db_float.in

when it should be something like:

net raw-float-switch <= parport.0.pin-12-in-not
net raw-float-switch   => db_float.in
net plasmac:float-switch   => db_float.out

or the equivalent:

net raw-float-switch <= parport.0.pin-12-in-not => db_float.in
net plasmac:float-switch   => db_float.out

also the debounce times were not set (so would default to 5 servo-thread periods so 5 ms)
 

I'm using proximity switches, so there is no appreciable bounce.  With the exception of the line you pointed out, this is the same HAL code I have used in several iterations of this machine -- and I've never had a problem with a lack of debouncing before.
I'm sure that the wrong joint assignment is the problem -- I'll know in the morning for sure, but the previous iteration of the machine worked just fine before I added the THCAD-2 to the machine.

I do need one or two of THCAD, but shipping will cost at least 3 times the price!
Just for kicks, ask how much would it cost to ship to Kosovo, Eastern Europe.
You should really be sitting for the answer, and having a cold beverage in hand helps, a lot!

tommylight wrote:

It is usually like that, no interest for a while, then all of the sudden several people gunning for them.
 

maybe you were right, the 7i80HD-16 is sold and shipped.
but i still have the THCAD-10 if anybody needs it.

i have a couple used Mesa boards i don't need, on my store website:
www.tjfhome.net/shop/index.php?route=pro...age=en-gb&path=66_68
i assume i set Paypal up right (USA shipping only)... if not, it won't go through, i guess. never had a purchase from my site yet to test it.
I have laid eyes on the 7i80HD-16, but the THCAD-10 i have not looked for yet, but know where it is.

7i76e_7i76x1_Dpl.bit is the firmware needed for a 7I76E and multiple THCADs

The load resistor for Ohmic sensing determines the sense current
I would not use higher than 25K

Note the if you use a lower value you need to make sure that you do not exceed
the resistors power rating with the open circuit plasma voltage.

Next I want to add ohmic sensing. With a Thad. 

I have downloaded the Firmware files from mesa. There are many files in the hostmot2 folder but have no idea which file I need to flash unto the 7i76E mesa board. What is the file name?

other question is about the serial resistor between positive and Thcad recommended is 390k but in one of the threads 25k is recommended can I freely experiment with resistors? Or does it need a high value to protect the Thcad?

You remember the episode lol, I was the one who bought thcad, and I had them held up in customs. Thank you very much for doing your best to get the plates to me.