CDPD with SMRID

The idea of this project was the SMRID has several sites that they monitor the water levels and flow rates.  Some of these sites are time consuming to get to.  They download the data at the sites with a computer onsite when they arrive at the location.  

The sites currently contain an level reader and a logger set at intervals to sample the data.  It then stores it up to a maximum amount.  Then when the data is collected the logger unit is reset.  The logger is in the middle and the float analog meter is on the lower right.

What we decided to try was Cellular Data called CDPD.  When you have an CDPD modem, it is assigned an internet IP address.  It has a serial port to communicate with whatever you wish, and in our case it was the logger unit.  There is some protocol issues between the logger and the CDPD modem but we where experimenting with an interface to take care of that.  If you look to the left of the modem you can see this interface.

Every site we encountered was able to get cellular coverage acceptable enough to work.  Some sites we did use a directional antenna such as a yagi until we were able to get a reliable signal.

Now once this system was setup, SMRID was able from there office, to log onto the internet, download the data, then process what they wanted to.  This would have a great potential to pay for its initial investment with the saving in man hours within the first couple of years.

We already had solar power for the other units at the site and it is able to support this cellular modem quite easily.  Its a self contained remote site that needs little or no maintenance.

These modems worked well once the system was refined and I think the test one is still in use to this day.

The applications could be endless from alarms, data collection, remote control, and the list grows.  The kicker is that you can access this from world wide locations where you have internet access!