I want to find a cost effective solution for connecting five stations on ethernet network using wireless media. Each station has a set of SCADA station and PLC connected with ethernet network. Distance between first and last station is 35 kms. All the other stations are in between first and fifth station.

 

Try Ethernet radios from DataLink or CISCO. DataLink have a radio can be a repeter to, then the distance could be not a problem. You can try free frequency radios (I don't know the regulations of your country), but this can be a problem if there is many guys using radio systems near your stations, usually in 2Ghhz or 5Ghz. Also can try radios in 900Mhz (usually regulated bands in many countries) to be more secury in your
frequency.
Good luck!!

Carlos Araya Mackenney
Automation Manager - PLC International S.A.
Phone (562) 269.8727 Fax (562) 269.8728
Santiago de Chile

 

> I want to find a cost effective solution for connecting five stations on ethernet network using wireless media. Each station has a set of SCADA station and PLC connected with ethernet network. Distance between first and last station is 35 kms. All the other stations are in between first and fifth station

Well, it will be "cost effective" right to the day when someone else interferes with your system. Then you'll understand why people bother to license such things.

Seriously, if your system can tolorate random communications outages, go for your unlicensed application. You stand a better chance of getting this system to work if your network is in a rural area.

I caution you that there is lots of market hype in this industry. Purchase your radios with care. If you ask questions like "What's the process gain of your radio?" and "How much throughput should I expect?" you ought to do fine. If you don't understand these questions, find a book on the subject and read it.

Caveat Emptor (And good luck!).

Jake Brodsky
[email protected]