Need help

Hello everyone,
We have installed turbine monitoring system with compactlogix 1769-L35e and a GSMmodem.customer was monitoring the system from his place. system is installed in a place where the network signals are very weak and too far from customer place. Now They are facing problems in monitoring the system because of weak network signals .First I thought of monitoring the data by using radio modems.in this scenario radio modem alone can't work because it's too far. Is there any way I can take the data via radio modem up to a place where there is network signals and from there it should transfer via gsm modem or is there any other way to do that please guide me on this if anyone have experienced such problems. Please guide me on this..


thanks in advance ..........

What sort of distance are we talking between remote site and where your customer is? Give me some latitude and longitude coordinates of both locations and I'll see what your options are.

Radio can cover well over 100km in licenced VHF and UHF bands if you have a high site for a repeater.

How exactly are they monitoring the data in the PLC? Is there a SCADA package pulling data from the PLC? More details on this end are required.

thank you saffa for your reply ,
distance will be more than 1000kms .Thats y am not able to work with only radio modem. Scada is pulling out the data from the plc remotely , currently this is done through a GSM modem.

Ok that is a decent distance, agree that radio isn't a good option.

Do you have a nearby high site with power and good cell coverage? If the GSM modem to PLC connection is over ethernet then you should be able to extend this using something like the Schneider Trio J series freeband radios (take a look on Schneider Electric website).

If the GSM modem connects serially to the PLC this can be more tricky depending on whether the PLC is handing the modem AT commands or not. The additional latency introduced by the radios can cause issues. In this case I'd buy another processor for your high site and use it to poll data from your turbine PLC over the radio link. The GSM modem is then connected to the high site PLC and the remote SCADA reads data from the high site PLC.

You say you have bad signal. Have you looked into some high gain cellular antennas for your modem?

we didn't look at that high gain antennas for the GSM modem .
if this doesn't work i will go with with the high site PLC option.
This will be helpful.

Thank you.