RS485 For Hypertherms

thefabricator03 wrote:

Rod,

What do you mean by a converter?

I kind of wondered the same, since it looks to me like you're using an RS-232 card with a DB-9 breakout board... ? Or maybe I missed something?

But alas, I did search RS-232 to RS-485 converter, and they do exist, and if nothing else, they come with a DB-9 breakout board that looks similar to the one you had used.

It may help to know what pins on a DB9 your breakout board corresponds to in your diagram. I think I tried about every wire combo I could think of though.

thefabricator03 wrote:

On Friday I will have a bit of time in the workshop so I will map the pin out of the DB9 plug and double check the model number of my PCI card.

I do remember having a freezing issue but I think it was when I was using the USB to RS485 converter. I probably should of taken notes when doing the testing

Sounds good, thank you. That works out, the converter isnt supposed to be here until Friday, so that's when I'll get back to testing.

In full disclosure I just got a cheap PCIe card, so in the end, that could be a problem as well.

rodw wrote:

thefabricator03 wrote:

Rod,

What do you mean by a converter?

Something like this
www.ebay.com.au/itm/DTECH-RS232-to-RS485...b:g:VWIAAOSwPqRayyD3

I assumed you had something similar that was part of your original USB version.

That's almost exactly what I ordered! Only mine had 5 terminals to handle Full duplex RS-485. It seems that one you linked was only half duplex RS-485. I am still a bit miffed though, as thefabricator03 doesnt picture a converter in any of his pictures, and I was confused how a RS-232 card would work from the beginning. It could be my card is just garbage as well.

He said hopefully he can pin it out on Friday, which is around the time my converter gets here, so hopefully I can get to the bottom of this

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.