Omron CJ2M PLC + gsm/gprs modem

[betilly0206]

Hello

I am new here and came for some help.
I working on project where i need to send a bit to 5 other plcs at the same time but this must be done wirelessly. I was looking for GDW-11 which is too expensive for mu budget. Is possible to realize this with something like that modem

http://www.ebay.com/itm/Q14576-USR-...632184?hash=item51e56f5eb8:g:WacAAOSwUuFWzqXD

or the GDW-11 is only way.

Maybe some other wireless solutions, the distance is around 200 m .

Thank you for any kind of help.

 

[gclshortt]

I have had allot of success with the following for wireless networks.
https://www.ubnt.com/
The NanoStation M is a good product.
https://www.ubnt.com/airmax/nanostationm/

How are you communicating to each PLC? Is the Ethernet port available?

Regards,

 

[betilly0206]

Now, the plcs dont communicate with each other. Now i need to send bit from "master plc" to other 4 plcs (example is trafic light green wave), when first intersection tell when next must turn green. One option is CJ2M plcs with free ethernet port(need to replace older plcs), and second with CQM1 plcs with free rs232 port. At this time this is realize with old CQM1 plcs.

 

[gclshortt]

http://gridconnect.com/wireless-rs485-wireless-rs232.html
It sounds like you need to set up a serial communication network. If you get a device like the link above on each of the PLC's this could be possible.
Each of the 5 PLC's would have to have a unique node address. (Host Link Number) This is selected usually in the DM area of the controller.
The master PLC 'CJ2M' will send and receive the information from the other PLC's.
Regards,

 

[betilly0206]

Yes, that is the way i need to go with. This means that i just need to configure adapters with different addresess and send data from Master PLC via command RXD and TXD to another PLCS. What about iterference via adapters, have any kind of success with them?

Is it possible in the later future to make some kind of data center, where you can monitor the whole process on PC with some scada on it right?

 

[gclshortt]

Each PLC will have a different address for the port that you are using. This is set up in the PLC. The adapters are used just to get the signals to the PLC.
A message is sent from the master. Every PLC on the network will get this same serial message. Depending on the address, only the one that matches will respond.
There can only be one master in a system like this.

Future monitoring is possible but this is not the way to do this. (Listen to the send commands only and write custom code to strip the information.) Unless you also send information from the master PLC somewhere.

You would be better off using the scada from the master PLC and insure that the information required is located there. I would use AdvancedHMI for this job.
https://sourceforge.net/projects/advancedhmi/
This is a free package that runs on visual studio.

Regards,

 

[betilly0206]

Soo if i understand in first(Master PLC CQM1_cpu21) need to set under plc settings Mode= [Host Link] Unit number[0]

On next plc need to set Unit number[1] and etc for other plcs. But which instruction then i need to use to send data to other plcs, cause txd send ASCII if i am not mistaken.
And this wireless serial RS232 will be used cause of my distance to the last plc(2000m)

http://www.tronicore.com/en/wireless-rs232-adapter

 

[gclshortt]

You are correct in the addressing.
This is a serial communication link. ASCII is sent out using the Host Link Protocol. (TXD) You will also need the (FCS) checksum instruction.
http://www.techtrends.ru/docs/omron/sistemy_avtomatizatsii/programmiruemye_logicheskie_kontrollery/kompaktnye_plc/programmiruemyj_logicheskij_kontroller_cpm1a/W228-E1-08_CQM-CPM-SRM_ProgManual.pdf

Yes you are correct with the wireless RS232. This is just the media in which the information will travel.

Here is a post that I did on the Host Link Protocol. It will give you an idea of how information is sent and received.
http://accautomation.ca/how-to-implement-the-omron-plc-host-link-protocol/

Regards,

 

[betilly0206]

Hm,i try to understand your post,but thats program in visual basic which i dont understand.I was searching on net and didn't find any example in ladder so i could understand. In manuals is just how to use instruction (operands, control word).

 

[gclshortt]

http://paginas.fe.up.pt/~pfs/recursos/plcs/omron/c200/op_manual/sec11a.pdf

Here is part of a manual that explains the host link protocol and the commands that need to be sent on the serial network.

Regards,