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Good afternoon

I will try to be as precise as possible about what I am looking for, although the language barrier does not help.

1st The 7i96s electronic board was designed with an encoder input ENCA+ ENCA-, ENCB+ and ENCB+. This would be the basics to connect an encoder with output A and B and for everything to work perfectly.

2nd I need to connect only and exclusively to ENCA+ and ENCA- a single frequency signal from the THCAD2 board that resets to 100kHz in the low position and resets to 1Mhz in the high position. This has already been done successfully.

3rd The big problem is that LinuxCNC does not understand that only a frequency signal from 100 to 1000Kz determines the feedback of the Z axis position.

I can't believe you don't understand this, given your extraordinary skill. Some people want to tell me that I ask questions that are too obvious to be answered by the masters. So I challenge the creators of this technology to prove that they can do this simple application by showing me examples.

Unfortunately, I really believed in the technology from the manufacturer MESA, and I received a lot of help from Mr. Peter and this forum. But it seems that now I have reached a limit where no one can help me with this. To make matters worse, I have not yet found anyone willing to provide the service, even if I pay. This is sad, because MESA has everything it needs to be widely used to replace major brands. All that is missing is more examples and support from professionals like me.

Since you asked what I want to achieve, it is simply to control a hydraulic cylinder that repeatedly hits a metal plate, but this hit has to be at the right height down to the millimeter. The actuation output is controlled by the 7i77 electronic board and it plays from 0 to 10 V positive to go up and from 0 to -10 V negative to go down. Next to this cylinder there is a linear inductive sensor that has a 0 to 10 V positive output that at 8 V is with the cylinder high and 0 the cylinder low, this height return with millimeter precision goes to the THCA2 board that sends this information to the 7i96s board, MY GOAL IS that in the G code I can control z000001.000 or z000001.50000 to drill deeper or less deeply. Did I understand the objective? Is there any better idea, or is it very easy and obvious?

After reading this several time i still can not figure out what you are asking! I am sure you are not asking for wiring as you can do that easily, so...
Would be much easier if you would tell us what you are trying to do/achieve/get to.
In short, the encoder velocity from the THCAD is feed to PlasmaC component (not GUI) where it is used to control the Z axis position during cutting, this all goes through a PID loop to keep the set voltage value inside the tolerances (usually +-1V) and the output of that PID loop is sent to external offsets component to do the actual motion of the Z axis.
There is much, much more to it, and for that you would have to go through the PlasmaC component on github, several thousands of lines of code there to explain what you are asking.

Good morning, friends

Does anyone have an example of how the Z axis is connected and controlled in the axis movement for controlling the height of a plasma torch using the THCAD2 board on the ENCA+ input of the 7i96s? I am developing it for other purposes, but I think the example can help. It needs to be in LinuxCNC 2.8.4, if anyone has an example, even a simple one, it will help.

 

 

Good morning Master PCW

I made the suggested change and it was not successful, an error appears, can you please help me?

The image below is before changing the line 214

 

The image below is after changing line 214

 

The image below is the error reported after the change

 

Attached are the error and hal configuration files


 

 

Please, can you help me?
 

One obvious change is that the Z axis feedback must come from the encoder velocity
(= scaled THCAD2 frequency)

net z-pos-fb hm2_7i96s.0.encoder.velocty
 

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!