Gantry oxyfuel / plasma type machine from scratch

Hi RodW, many thanks for answering. Seems you are telling me to use an EtherCAT Beckhoff module for the THC ?

Should I be using only Beckhoff modules or can I go with any other producer, there is a lot of stuff out there. I was evaluating Triomotion modules for motion controll, IO and Analog IO. The Flexslice series ( www.triomotion.com/public/products/flexsliceExpansion.php ). Seems they should work with LinuxCNC.

Hi NWE, thanks for commenting. Can you share more details on what are you looking for to use for the retrofit ?

saxa wrote:

I see the board has only one input for the encoder feedback. But I have 3 drives, so should I leave the encoders
signals from the drive to linuxcnc out ?

Yes you should leave them out, as noted above the only usable way for DMM drives is in Position mode as they have a delay in position signal outputs.
Also the encoder input will be used for THCAD if you want plasma.

saxa wrote:

Or there is a way to connect all 3 encoders to the board ?

Yes there is, Mesa 7i85 or 7i85S should have 4 encoder inputs.

saxa wrote:

Also has LinuxCNC some settings to make the preheat , and open the various gasses vales at ceartain time already in or should I be doing this from zero up ?

No, not per se, but LinuxCNC can be programmed as you need it, so a simple G04 P1800 will make the machine wait for 30 minutes at the first cut to preheat the material.
Same for outputs and solenoids, everything can be automated and even add a side panel with settings and buttons and stuff.

Ethercat is very good for motors, but for slow I/O is only expensive and modbus may be better choice...

 

saxa wrote:

Hi RodW, many thanks for answering. Seems you are telling me to use an EtherCAT Beckhoff module for the THC ?

Should I be using only Beckhoff modules or can I go with any other producer, there is a lot of stuff out there. I was evaluating Triomotion modules for motion controll, IO and Analog IO. The Flexslice series ( www.triomotion.com/public/products/flexsliceExpansion.php ). Seems they should work with LinuxCNC.

Linux-CNC is the Ethercat master. You just need ethercat slaves. Have a look at the Beckhoff EK1100 and the many various modules that attach to it. Many of these modules have native support in LinuxCNC. There may be other brands of modules available but you would need to write the driver and you'd need to be sure they have 500v or so over voltage protection in case something goes wrong. Beckhoff and Mesa have that.

saxa wrote:

Can you share more details on what are you looking for to use for the retrofit ?
 

I have not yet started shopping for servos for my machine, but I plan to use ethercat servo drives. I'm thinking likely Stepperonline or Lichuan or Delta brand. For I/O I expect to use Mesa or Beckhoff EK1100 with EL1809 and EL2409. I've used both in multiple projects without any problems that I can remember.
If connecting multiple encoders I nearly always use Mesa because Beckhoff encoder counters are so much more expensive.

For slow cheap I/O I used to not like modbus, but tried it some more recently and am pleased how it is performing. This would not do for limit or homing switches, for those you'll want ethercat or Mesa for sure.