The GP-4210-TM'"s RS-485 DB9 wiring connector diagram is shown below.



It's 4-wire RS-485. 10 years ago, a guy who wrote code for gateways (Linse) mentioned potential problems with wiring 4-wire RS-485 masters as 2-wire (jumpering the driver lines Tx(+) jumpered to Rx(+); Tx(-) jumpered to Rx(-)
in this thread: http://www.control.com/thread/1370343245

You might ask Proface support if the Proface RS-485 port either
- keeps the RX pair ON all the time or
- Tx drivers are kept ON all the time

There's some reason that there Data Terminal Ready connections: DTR(+) (pin 4) or DTR (-) (pin 9)

 

I think we found the solution to your problem.

The SG is the GND line of the RS-485 connection.
You must use that for the communication.
Please consult the hardware manual page 36 for the connector, your unit has only 1 connector so you need COM1 in GP Pro Ex.
See: https://backend.proface.com/media/48922
In order to get the communication going (and enable the interface internally electrically):
Connect 1(RDA+) to 3 (SDA+) this is the A line
Connect 2 (RDB-) to 7 (SDB-) this is the B line
Use 5 (SG) for the GND of the RS485.

Not, in order to enable the electrical interface, the following extra bridge connectors must be made:
Connect 4 (ERA) to 8 (CSA): use a bridge wire between 4 and 8. This enables send possible A+
Connect 9 (ERB) to 6 (CSB): use a bridge wire between 9 and 6. This enables send possible B-
View attachment 3796

Please try that and let me know.
gr. Patrick

Dear Patrick,

thank you so much, it worked. I really appreciate your help. I was stuck in this issue since one month ago. I reviewed everything, I looked for information on the websites and forums. Because I like to try it by myself before asking for help and because I did not know what else to do, I found myself in need of ask you for help and also to Pro-Face Support Team.

Just one doubt. How did you know this two bridges were missing in my configuration?

Best regards,

Jose Espinoza

 

Shame on Proface tech support for not recognizing this wiring/enabling issue with Modbus on their own HMI's.

 

Glad that I could be of some help to get it working.

Pro-face uses 2 types of ports. Some only have the A, B and GND signals, those ports are for example for Canbus//Profibus. There you don't need to put the enable jumpers.

I always check the hardware manual for specific Pro-face touchpanels. When I checked the comport of the one you have I immediately saw the enable lines and I know from my 13 years of experience with Pro-face that these often cause problems. Just add a few bridges and you're fine.

Now make sure you use 120ohm impedance corrected cable like the Lapp Unitronic Bus LD. That is specifically developed for RS-485 connections. Can be ordered per meter from Conrad.
On the last module in your RS-485 network, install a 120ohm resistor between the A and B line.
This way you have a reliable and rugged connection.

And regarding the support of Pro-face. Sometimes I think I know much more about those products then themselves......especially the D/Gscripting that is -very- powerful, combined with the ladder logic.
You can make complete control systems without having to add a PLC.

I would appreciate it very much if you would browse through some of my Pro-face projects I developed over the years for temperature control.
See: https://cascade.net/en/custom-solutions/

 

That's a lot of nice application packages.

That RKA SB1 is nice little electric heater controller. I like the combination DIN rail/flange-wall mount option with brackets for pipe mounting, something none of the vendors offered when I was spec'ing that stuff.

Did any of your customers ever use the non-Modbus protocols?

Any chance you know what the input spec "influence of external resistance: 0.25μV/Ω (Thermocouple input). Where is the external resistance coming from? is this a reference to the resistance of thermocouple wire or extension wire (which quite high compared to copper wire)?

What's it cost to get the Comm adapter and config software?

 

Dear David,

Yes, we have been busy over the years.

The RKC Instrument SB1 is specially developed for heat-tracing applications. Therefore it is fitted with an internal solid state relay. You can install it near the pipe to be heated. Connect the 230V heating element, 230V power supply you're ready. We developed a Pro-face application for it so in the central control room a panel can be installed for operating these controllers. This Pro-face panel can be remotely accessed with the standard Pro-face app on smartphone/tablet/windows PC.
Nice is that it can also be installed on a DIN-rail, but also directly on the pipe with a band around the pipe.
It is used in various semiconductor factories and some food- and feed- plants.
See: https://cascade.net/en/heat-tracing-temperature-control-and-monitoring-with-remote-scada-hmi/

Some customers like a more centralized approach, for that they use our RKC Instrument DIN rail mount SRZ system, see: https://cascade.net/en/srz-system/
1000s of these modules are used, everywhere.

Almost all of our customers use the RKC Instrument controllers with their Modbus protocol. Only a very small group uses the standard RKC Instrument ASCII protocoll. You can switch it inside the controller.
Our SCADA software "SpecView" can communicate with them in either interface type. You can make nice PC-based SCADA applications with it using a few clicks to get the communication going. Specially developed for engineers that don't have a lot of programming experience and for people that just want to read-out and record some temperatures incl. recipe management. Many Unilever food-factories use this software worldwide. See: https://cascade.net/en/scadasoftware/

The specification you're referring to is for thermocouple wire, since it has a different resistance/meter than copper wire that is used for extending the thermocouples.
RKC Instrument excels in temperature measurement with thermocouples in extremely noisy environments. I've seen many other brands fail next to frequency inverters and thyristors. But not RKC Instrument. RKC Instrument controllers have no connection for PE/earth, because in Japan there is no proper earthing possible because of its rocky soil.
Because of this, RKC Instrument thermocouple measurements are very accurate & reliable and not sensitive to external noise.

The PROTEM2 configuration software can be downloaded for free, see: https://www.rkcinst.co.jp/english/download-center/?dc_cat=10 and click on the software tab. There you find the PROTEM2 software.
The COM-KG is 175 euro's.
See here the COM-KG: https://cascade.net/en/com-kg-communication-converter/
But if you order large quantities of controllers there is always something that can be arranged of course.