RS485 For Hypertherms

rodw wrote: I think Stefan the fabricator started with this USB interface but found it was not reliable.
www.jaycar.com.au/usb-port-to-rs-485-422...signal-rate/p/XC4136

I think then he bought a RS232 card for his PC and used the RS485 side from the converter above.

I've attached the Hypertherm docs which included the wiring diagram.

Serial comms Is pretty simple really. Transmit (TX) on one machine connects to Receive (RX) on the other machine.

Thanks for the attachment, I had the old version, I couldn't find the rev'd version! Although from what I see the pinout is the same.

Anyways, good news, my adapter showed up today! So I will be doing some testing after work. Hopefully it just works lol

Ok, good news! Rod was right, I needed a RS-232 to RS-485 converter. I'm going to try to give as much info about my setup as I can, and then maybe someone can more easily replicate it. I have no idea why Stefans works without a converter, I imagine his card can actually do RS-485 comms.

RS-232 Card (dont believe the hype it doesnt do RS-485, at least not that I can figure out):
Card

RS-232 to RS-485 Converter:
Converter

One thing to note was that the DB9 Break out board that Stefan used and the one that I used are different when read from Left to Right. I would imagine they pin out the same way.

Stefan's (Left to Right):
1: T/R-
2: T/R+
3: RXD-
4: RXD+
5: GND

Mine (Left to Right) - corresponding DB9 pin listed after:
1: T/R+ ==> DB9 Pin 1
2: T/R- ==> DB9 Pin 2
3: RXD+ ==> DB9 Pin 3
4: RXD- ==> DB9 Pin 4
5: GND ==> DB9 Pin 5

Connection to Hypertherm is as he suggested. Hypertherm is on the left:

Tx+ => RXD+
Tx- => RXD-
Rx+ => T/R+
Rx- => T/R-
GND => GND

After that it just worked.

Some bugs for Phill to squash:

For the Port tester code:
1. The default values will cause an error since they are out of range for most of the Powermax's. I would suggest making the Default Amps 40 and pressure 75. Something that is in the range for even the 45 amp model.
2. The max pressure for gouge mode is different than the other two. It's 3.0-4.0 Bars, or 43-58 psi. It isn't a huge deal, it just causes a remote controller pressure error. I am not sure if you set this manually in the code, or if you read it from the machine. I think the latter is possible from what I read in the protocol manual, so maybe there is an error in the code there?
3. I dont think the Powermax can handle decimal places for PSI (BAR it can). I also wonder if it can handle decimal for AMPS as well, but I do see that the Serial Manual from Hypertherm does give 55.5A as an example.

For the Plasmac GUI:
1. When comms are enabled, the tooltip for hovering over Amps should change to say that this controls the amperage for the plasma cutter or something to the sort, currently it says it's just reference, which is true when the comms are off.
2. I dont think the Powermax can handle decimal places for PSI (BAR it can), I wonder about AMPS too, see #3 above.. I know it cant display it for sure, not sure if that means it's irrelevant when cutting or not.
3. It might be nice to note with a tooltip over the Pressure that a setting of 0 will set the gas mode to Automatic mode. Likewise, the pressures should mimic the min and max from the different cut modes.. Meaning it wont let you enter a psi of less than 43 for gouging mode, for example. (again I think maybe you can read this from the machine?)
4. Where do error messages show up in the GUI?

Anyways, I am so excited I got this working. Thanks everyone for the help, and as always thanks to everyone who contributes to making this interface great.

Since you are talking about RS232 to RS485 adapters, a while back someone here showed a strange RS232 port with a small board and a ribbon cable, i found them, some 10 of them, so if any one needs them, i will gladly mail them free of charge, if the post office does not require an arm and a leg for it.

I'll take all that on board but I'll wait a while and see if Stefan has any comments.

It is a bit difficult for me to test as I don't have a RS485 machine, I just have an Arduino with Phill's interpretation of a PM.

I don't recall what the defaults were for the port tester and Stefan did all the testing on his PM125 but i see what you are saying.

The Max and Min are read from the PM on successfull connection, does the PM change these values on the 485 link when the mode changes?

I have no clue about the decimals as I don't have a machine to check.

Error messages appear in the Powermax Comms box on the Run Panel as well as a popup dialog.

phillc54 wrote: I'll take all that on board but I'll wait a while and see if Stefan has any comments.

It is a bit difficult for me to test as I don't have a RS485 machine, I just have an Arduino with Phill's interpretation of a PM.

I don't recall what the defaults were for the port tester and Stefan did all the testing on his PM125 but i see what you are saying.

The Max and Min are read from the PM on successfull connection, does the PM change these values on the 485 link when the mode changes?

I have no clue about the decimals as I don't have a machine to check.

Error messages appear in the Powermax Comms box on the Run Panel as well as a popup dialog.

Honestly I think it works pretty well. Didn’t mean to suggest otherwise. Impressive you used an arduino to emulate the PM to get us this far.

As for the min and max I’m not really sure, but my guess is that it does change the value available to be read on mode changes, since the min and max do change for Gouge, and the PM shoots an error until you go below those values. If you want me to test some code I’m happy to.

I’m not sure about the decimals either as far as if they mean anything to the PM or it just accepts them. For sure it can’t display them. Overall I find it hard to believe .1 of an amp matters a whole lot in our application either way. I just wanted to report back on what I was seeing, so the displays and the software were congruent. Just was a thought.

Good to know on errors.

Thanks again for the work you put into this. As I said before, I seem to have a knack for breaking code/finding bugs.

Is your installation Buildbot or RIP? If I do some code changes I'll try to give the correct instructions for you to install them.