I was hoping someone could provide a chart coarsely describing the pros/cons of different communications media for water/wastewater SCADA applications... Cost to install, Cost to Maintain, Reliability, etc. Dial-up Leased Line SS Radio Licensed Radio CDPD Etc. Any help would be appreciated.

 

> I am also looking for the same information; specifically, cost per node. I am thinking that the node consists of the translation device in the head of the transmitter; analog to digital and any connection to the fieldbus. What would the cost of the device, its installation and calibration be? Are there any other costs involved? I am trying to compile a comprehensive list combined with performence data as a selection guide.

 

I am curious if anyone has tried to contact you on this. I have looked into various sources and have nothing worth taliking about. However, I think in a little bit of time we could compile some good information.

 

I am also looking for the same comparison and doing some research on it especially regarding use of CDPD technique in SCADA applications mainly water/ sewerage, and if I would be able to find some useful stuff I definately post here, otherwise anybody's help in this regard will be highly appreciated.

regards

 

Here is my 2 cents' worth. Leased lines are great if the local phone company has their act together. I have a customer who replaced their leased lines with UHF licensed radios because of poor service from the phone company. I also have a customer in a different city using leased lines and they have very few problems. Leased line modems cost more than dial-up modems. And I think leased phone lines cost more than dial-up lines. But, on the other hand if all you want to do is collect status information once or twice a day from many stations dial-up modems would work fine. Also,auto-dialers available on the market can be configured with analog and digital control, to send alarm info and receive commands via telephone, etc. They are very sophisticated. Radios work great when the system is designed, installed, and is maintained by a competent person. SST or UHF licensed radios. With any radio system a comprehensive site survey is necessary to insure proper coverage and performance. Without that it is a
crap shoot. A lot of water/sewer sites don't have access to phone lines. So radios are a good answer. Don't forget cellular and satallite
communications either. You can hook up a modem to a cellular or satellite phone and get dial-up like service. Again, there is a monthly fee for the service but if a phone line isn't available this is a good alternative to radios. Radios need to be maintained, but there is no monthly fee for using them like there is with phone lines or cellular, unless you need to lease a repeater antenna site. So the cost of the radios can be offset by savings on phone service. All these technologies can work great if the system is designed, installed, and maintained properly.

 

HI DAVID

Did you get something about media comparison, if so would you please contact me thru my e-mail: [email protected], your help would be highly appreciated in this regard.

best regards

Danish Siddiqui