Communication between M172 and TM172DCL

[Anonymous user]

Hi,

I am trying to connect TM172DCL (Display for M172) but I keep getting Modbus Comm error.

Current Setting:

1.  I am using RS485-2 as a Modbus Master on M172.

2.  Created a Generic Modbus Device for TM172DCL.

3.  Since they both have the same power source, I left ground disconnected.

4.  Installed 120 ohm to TM172DCL.  Maybe I need to install 120 ohm on M172 as well?

Can you tell me what I am doing wrong?  I need to be able to exchange variables between them but It seems that RS485-2 link on M172 is dead.

Thank you for your help!

Jung

[LeTomas · Accepted solution]

Hi @Anonymous user ,

When I work with the M172D I usually use it as a master in the communication because for me is much simpler to exchange the information between the devices.

Take a look on this presentation of how to connect both devices (M172 plc as slave): 

https://schneider-electric.box.com/s/ld78b6pxs08l0tb7qgz3eix01hha5wpt

Project: https://schneider-electric.box.com/s/kcwhv7kxtat0shm20njyzzc87azx4dkk

In your case if something is not working you should try to check:

1) The connection from the M172 RS-485 2 to the display (you can check the connection in my presentation but with RS 485-1).

2) The Actual values on the modbus configuration on the M172D and the PLC (They must match).

3) Verify the registers that you want to read from the M172D.

I hope this helps you 👍

[Anonymous user]

Hi, @LeTomas 

Thank you very much for your help.  I followed it and everything is working fine now.

Jung

[Anonymous user]

Thank you for sharing your experience it is very useful, I'll keep in mind this.

[Anonymous user]

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[jf_graphen_pl_b]

Hello LeTomas,

I have to connect TM172DCL with AS-P. I think that it is possible ,but so far I could not   force  my TM172DCL communicate with a Modbus slave which I have in AS-P. Maybe it is because I haven't difined AS-P in M172 project. But how can do it? Must i do spoofing AS-P as M172 device?

Maybe you another way to use TM172DCL as simply Modbus display in Ecostruxure system?

Could you help me?

Best reagrds,

Artur

[Bastian_Schmitz]

Hello Artur,

If I understand you right you want to use TM172DCL as Master an AS-P as Slave?

If yes you have two possibilites.

1. Program the communication directly with the integrated Target Blocks sysMbMRTU_FC** and activate in RS485 configuration the master function

2. Generate manually a *.Parx file to exchange the variabeles between TM172DCL and AS-P automatically. These must be done manually. You find in every TM172P project a *.Parx file as example. The *.Parx file is for the data excahnge between PLC and TM17x HMI.  

best regards

Bastian

[jf_graphen_pl_b]

Hello Bastian,

Thanks for help. It directed me to another setting which I didn't set -

So for I used the second methode , I set Remote mode in HMI Parameters Management , slave address in bios parameters , but didn't change to Master in RS485.

But now , after downloading  i lost communication with device. Its understood , i see  that display reads from my server (slave).

But how to reconnect to download new version? Excuse , I'm still green in this soft 🙂 .

Greetng, Artur

[jf_graphen_pl_b]

Hello again,

I have another question. Is is possible to display strings on M172 DCL's wiiach are working as Modbus slaves?

I can display  string  on one master (strictly one master M172 DCL can take string from slave e.g.AS-P),but I have some DCL displays on one RS-485 bus and must to display different things on them.

Is it possible? 

[Bastian_Schmitz]

Hi Artur,

I worked last time a few month ago with TM172DCL. So I´m not fully sure how was the process.

But in my opinion it should be possible to connect via Micro USB cable, if the Modbus RTU Master is running. 

Did you use a MicroUSB Cable or did you use a USB/RS485 Adapter? The connection via RS485 is impossible if the modbus master is running.

And if this will not work try to connect directly after power on of the Display. Mostly the Modbus Master starts first after a few secondes. If you connect before the master is startet you could update the Programm. 

best regards

Bastian

[jf_graphen_pl_b]

Hi, Bastian

  That is correctly as You wrote. Thx for help. Classical RTMF case 😉 but for M172 there are no manuals ,only films as i know.

 And "private invastigations" :).

 Greetings, Artur

[Bastian_Schmitz]

Hello yes this is possible. But you need to rebuild the string on TM172DCL. Because modbus support "only" modbus communication which is designed for 16bit values. Please use the follow function

Basic Addons Word16toString31 

[jf_graphen_pl_b]

Hello,

Thanks again, 

I nearly have this. But I think it is a shame to SE to persistent unsupport of block writing in modbus. With this my problem is a banal one.

As I wrote , I'm a newbie with M172 and my fight with this is just a time waste.

I know at least another one case where lacking of block write operation make makes service  provided by ESBO AS lame. I naive thought that ESBO 3.2 have this option .....

Greetings, Artur.