SJDrummond's CNC Plasma Wiring Diagram

[SJDrummond]

Hi all!

I have recently been upgrading my CNC plasma electronics from a Openbuilds Blackbox 4x to a MESA 7i96S as I realised just how important THC is. In the process I have created this wiring diagram and thought it worth a share in case anybody else finds it useful.

Please note: V0.1 is a working progress and may contain errors, use at your own risk. I have no official training in electronics design, however I have built a couple of 3D printers successfully and this will be my second table.

I would love and really appreciate any feedback on the diagram, good and bad. Particularly if you can spot any errors or things I have missed.

I plan to update the diagram as I go and once I have a successful diagram, I will promote the version number to V1.0 and add lots of pictures of the design.

All the best,
Sean

CNC-Plasma-Wiring-Diagram.png

[acourtjester]

HI Sean
I have a similar setup using the Mesa 7I76E board that is on a back burner for now but would love to get some info from you in the future. Are you using Linux software or something else. I have it functional except the Ohmic sensor section, with guidance I was using a slightly different circuit than yours.
I have built 8 other table using other controllers and software, but am a little in the dark with Linux.

[SJDrummond]

Hi Acourtjester,

Ofcourse, feel free to contact me through this forum, Il be as helpful as I can be, although it is also my first venture into the Linux world.
I am in the process of setting up QTPlasmac and SheetCam.

For the hyper sensing part, I have based the design off of the Plasma Primer for Linux CNC (linked below), which if you haven't seen yet, I would definitely recommend. There's plenty of other really useful info on there. Im pretty sure that @Rodw was the mastermind behind it.
(linuxcnc.org/docs/stable/html/plasma/plasma-cnc-primer.html#_hypersensing_with_a_mesa_thcad_5)

I would be interested to see how your circuit differs.

All the best,
Sean

[adbuch]

That wiring diagram is very professionally done. I'm sure it will be of interest to other members. Thanks for sharing it.
David

[SJDrummond]

Hi David,

Thanks very much! Just hoping there's somebody with more electronics expertise to give it a quick once over!

All the best,
Sean

[acourtjester]

thanks Sean I will get back to you when I pink up that table's finishing process (all is done but the base). I have communicated with Rodw and he has been a great help. The last video of his a watched he was talking about some changes to QTPlasmaC with new buttons. On the Hypersensing there seems to be lots of discussion on the LinuxCNC about whose right and whose not. Here is the circuit with the difference marked with the arrow, and the other based in your schematic. My problems is with the software (setting up Pncconf for the hal and files) to function correctly.
Images of part of my controller cabinet.

Ohmic.JPG

Ohmic sensor circuit.JPG

DSCN4723.JPG

DSCN4799.JPG

[adbuch]

Following with interest.
David

[SJDrummond]

Ah, I haven't seen that diagram before. Once I have mine built, I will let you know if it has worked or not.

On the Hypersensing point, just checking some other forums and came across this by @tommylight:

"Having two or more THCAD connected to Mesa 7i96S or 7i76E requires flashing the firmware using mesaflash.
The firmware for Plasma will have the letters"pl" in the firmware name together with the card name."

Have you re-flashed the firmware to this file?

Another user seems to have had success with the following @Dhoerauf:

"I had a chance to connect everything up today and test. 7i96s DPL firmware, linuxcnc 2.9, QTplasmac. The OHMIC hypersense with THCAD-5 works great."

I know you're working with the 7i76e, but I would assume it translates across the same?

Your electronics look very clean!

Here's my build so far, however once putting it together I am concerned its a little too compact and is going to require some heat management haha. Im hoping the inlet and outlet fan will be enough. Each stepper driver has a 40mm fan built in to the heatsink so I'm hoping that will dissipate the heat into the cabinet and then the air flow will take it out the box!

Best,
Sean

SJDrummond-CNC-Plasma-Electronics-Build130922.jpg

[acourtjester]

Thanks SJD I had not seen this before
("Having two or more THCAD connected to Mesa 7i96S or 7i76E requires flashing the firmware using mesaflash.
The firmware for Plasma will have the letters"pl" in the firmware name together with the card name.")
I had gone with a different approach after stumbling with the Hyersensing with another circuit for the Ohmic sensor. It worked well but I did need more testing. I have it on my other table and it worked great for both Plasma and routing touch off. I was looking around my HD and found this I had save, does it look familiar.

Sean D.JPG

[SJDrummond]

If you find that firmware file, could you link it on here for me? I can’t see to find the file anywhere.

That doesn’t look familiar to me - must be another SeanD on the forum!

[acourtjester]

here it is

Using Z Probe With LinuxCNC _ SeanD.pdf

[SJDrummond]

Sorry Acourtjester, is that the firmware file to enable the second (and third) encoder pins on the MESA boards?
Best, Sean

[acourtjester]

I think I combined 2 thought that were unrelated, The image was of a page in the PDF doc. and the attached is that doc.
I don't have the firmware file but would need it for the additional THCD boards. On my Linux setup I am using a different circuit for the OHmic sensor, not the Hypersensing circuit.

[SJDrummond]

Ah I see now yes.

If anybody else has any instructions/info on how to flash new firmware (and where to find all the firmwares). It would be greatly appreciated!

[LucasWorx]

Thank you Sean! This diagram is extremely helpful. I am nearing the end of my table build and my setup is almost identical (45XP, 7i96, THCAD-10, etc). I wired my fast blow fuse inline with the #3 pin on the CPC port going to the Mesa's output. Your drawing is showing it on the number 12 pin. Could I have mine in the wrong place? I think the Mesa commX2 you have is throwing me off. Is this just for added inputs? Any help is really appreciated. This is all new to me so forgive my ignorance if I'm looking at it wrong.

EDIT: Nvm I now see that the Mesa commX2 is basically just a terminal block for distributing the 24V. My question still remains about which pin to have the fuse on though:/ I thought the #12 pin from the CPC port would go to the E-stop.

[SJDrummond]

Hi Lucas, thank you! Glad it was some help!!

Happy to help where I can but please know I have no electronics training and I haven’t finished building my electronics yet.

Yes you are correct about the commx2, it just extends the 24V power supply to allow more connections.

Pin 12 according to the Hypertherm PM45 XP manual is ‘Transfer (Start machine motion)’. It looks to me like internally it could be a relay. When the plasma cutter has made a successful arc, it tells the Mesa board that it is okay to start moving. Which I think it does by allowing power to flow from 24V Field Power into the Mesa board - Input 10. I wouldn’t have thought that would have been the correct place for an E-Stop if I’m honest, but happy to be told otherwise.
All the best, Sean

[LucasWorx]

Hey thanks for the swift reply Sean! I think you're right. I was referencing another user's diagram that also had the 45XP but the more I looked at it, it didn't seem right. The more I looked at yours, the more it started making sense. I plan to post a short write up soon when I finish my build but hopefully in the next few days I'll have time to run through the PlasmaC configurator. It seems like every time I search for an answer to one of my questions, I end up with 3 more questions! Lol. Steep learning curve on this stuff for sure but I'm enjoying the hell out of learning it. Thanks again for your time an effort into that diagram.

[SJDrummond]

Haha I very much know that feeling, Very steep curve but very rewarding and worth it!

If you have any more questions I might be able to help with, do let me know.
Best, Sean

[acourtjester]

Not to butt in but I found it is easier to redo the configurator to make corrections then changing the lines in files. I just gave it a new name for each time I did them.
there is so much that is in the configurator like screen size, motor pins, direction, speed, homing switch pins, travel distance, number of steps, so much more too. Are you using QtPlasmaC.

Z 1 driver.png

Z 2 driver.png

y driver setting.JPG

[LucasWorx]

I myself will be using PlasmaC since I am using Linux 2.8 but I will update at a later time. I'm still trying to learn and set my scaling options correctly through pncconfig before moving on to the PlasmaC setup. Currently having a hard time finding the right scaling options and info for my DM556 drivers.

[acourtjester]

Hi Lucas I sent you a Private message from here which may help with the scaling
have fun
Tom

[SJDrummond]

Hi Tom,
Im using QTPlasmaC on Linux v2.9. Once I have a working configuration, Im hoping to post that here too as a bundle when its working.

[acourtjester]

I am using Debin 10 and had a problem with the Hypertherm tool conversion routine for QTplasmaC

[SJDrummond]

Hi all, bit of a progress update!

I've decided I really want this project to be a 'best practice' type document & I have been working with @Rodw to improve the diagram.

So I have:
- Incorporated an Emergency Stop system into the design using a safety relay (Pilz Pnoz X2.1) and a contactor to cut power to the Stepper Motor Driver power supply and send a signal to Linux CNC to stop all motion.
- Swapped a number of the GX16 connectors for one DB15 connectors for all the limit switches and ohmic sensing in an attempt to reduce the number of cables leading from the box to the machine.

CNC Plasma Wiring Diagram V0.5.png

I have a couple of questions if anybody could help?

1. Do I need a solid state relay between the MESA 7i96 and the PM45XP Start signal?
The documentation says
"Normally Open.
18 VDC open circuit voltage at START terminals.
Requires dry contact closure to activate."
In theory the 7i96 has relays for all the outputs, but my electronics knowledge doesn't stretch far enough to know if its suitable?

2. Does the 18VDC in the above refer to the required voltage to activate? I only have 5V and 24V DC available at the moment, Will I need a separate power supply for this?

3. Am I correct in thinking the ENA+/- Pins on the drivers should go to the 5VP and GND of the 7i96 STEP Pins(as pictured)? Or should they go an output?

4. For the THCAD 5 (Ohmic Sensing), I have currently taken power/ground from the STEP 4 pins. But I think this is incorrect. Where would be the best place to take these from, can it come from the MESA 7i96 somewhere? I have seen when people use a 7i76e, Encoder B has separate GND and 5VP available, however the 7i96 doesn't. I do have a separate 5V HDR Power supply I could use, but Rodw said he didn't think it was necessary to have an isolated supply. Any ideas?

Thank you!

All the best,
Sean

[acourtjester]

Hi Sean
I am using a 7I76E card for the controller so some differences, but not large. I use a external relay to trigger the Plasma on and it is just a switch contact the 18 vdc is internal to the Hypertherm. Meaning you can just touch 3 to 4 in the connecter to fire the torch.
Here is a pin ID for the 7I96 that may help. RodW is a great help, he seems to give clearer info then the LinuxCNC blog.

7i76e pin info.pdf