Radio Modems

[ECSI 17]

Hello I am working on a new project and require radio modems. I have a CS1G PLC at the central location and I'm using CX-Supervisor as the HMI. I need to go out and poll 3 other PLC's at remote locations (most likely CJ or CPM2A). None of the remotes exceed 3 miles in distance from the main CS1G. I've never used radio modems and would like to hear some recommendations on which manufacturer to go with. Any comments would be helpful. Also, I need to get data from an AB SLC5/03 to the SCADA. They are side by side in the building. I am thinking of going directly from the computer to the SLC by RS232 cable and using RS Linx OPC server software to tie the AB points into CX-Supervisor. Have any of you tried this? Is there a better way of doing this? Thanks Paul

[Sleepy Wombat 27]

ECSI, sounds like a fun challenging project....... In the past I have used Elpro Modems, they are an Aussie company that has been around a fair time and are making huge inroads in the World Telementry market. Ther link to their web site is .... Elpro Radio Modems I beleive that you are from Canada - There are four distributors in Canada. The model you would be using is the 905U-D. As for the AB thing the OPC thing sounds interesting but may I suggest another solution....How about adding a Devicenet Master to the Local CS1G and a DeviceNet Slave to the AB PLC's. Omrons implementation of Devicenet is the best and easiest to configure especially when using auto allocation. I know this works. Depending on how much info that you want to get from the central CS1G PLC might i also suggest that you get an ethernet card for the CS1 also... Hope that helps Sleepy Wombat (Coffee Time)

[ECSI 17]

Sleepy, Thanks for the lead on the Elpro modems. I'll check them out. I also found an interesting gadget called a Gateway Protocol Converter. It seems to transfer data directly between plc's of all major vendors. You can find it at: www.renuelectronics.com/gatewayoverview.html As for the devicenet suggestion, I don't really want to add any hardware to the AB plc since it is being supplied by a competitor and it may cause warranty conflicts. I figure using OPC or the above adapter may be the safest way to go here.I only have to monitor about 40 words of data. You're right, ethernet is a must on the CS1 system. Speed is everything! Paul

[Guest Gili]

I have used in the past the following solution for a similar problem. Several Ethrnet-radio hubs where located (up to 10 kilometers) one from the other (AP-10 pro and SA-10 pro from BreezNet). For serial communication each ethernet end was connected to serial/ethernet converter (I used MSS-1T) each given a diferent IP address. The netwark can be also used for several computers and direct connection to ethernet adopters. This allowed transparent network from the main PLC or computer to the others. The total bendwidth was about 3 Mbps. Ithink today you can get better. Please note that some industrial interfeerence can affect the operation of the netwark. Second note is that the ethernet/serial devices need some settings for proper operation. Gili

[Sleepy Wombat 27]

ECSI, just got back today and remembered another supplier in the States that has done a lot with Omron with radio links (ethernet included)....Data Link modems. Datalink Modems Link Edited 30 Nov 2003 by Sleepy Wombat

[Jay Anthony 118]

Here are some reviews on DataLinc from the MrPLC.com links section: DataLinc Radio Modems

[ECSI 17]

Thanks guys. DataLinc seems to be highly recommended by a lot of people. They seem a little expensive but I'll probably give them a try anyway. Its better to try something with proven success than to go the cheap route. Paul

[Sleepy Wombat 27]

Paul, I look forward to seeing how you got on ... could you let me know how you go..Thanks ..Sleepy Wombat

[OmronFAQ 0]

We have investigated the linking of two CS1G's via Datalink Wireless Ethernet units. The support from USA to Australia was very prompt and the information provided was spoton. They do appear to be expensive but what price do you place on a reliable industrial network system We are yet to install this system but will update when applicable.

[ECSI 17]

Well, I took Sleepy's advice and went with the Elpro radio modems. They were very easy to set up and are working perfectly. Good old Aussie technology...and I didn't even have to mount them upside down! As for the AB communications, so far I'm having no luck with the Gateway converters. To be continued..... Paul