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Subscribing to measurements received by openPDC

Dec 6, 2012 at 12:36 PM

CONTEXT:

I have openPDC 1.5 installed (as a Windows service). I run the openPDC manager and I can see in "Graph Measurements" that I am getting data from a device (PMU) that I have configured with the Input Wizard. The data is archived by the default historian PPAREADER somewhere on the hard-drive.

WHAT I AM TRYING TO DO:

I want to subscribe to new measurements received by openPDC using a code similar to the TimeSeriesFramework example from the documentation:

http://timeseriesframework.codeplex.com/SourceControl/changeset/view/61589#1011313

DETAILS/PROBLEMS:

My connection string is: "server=localhost:6165". I have noticed that in openPDC Manager there is a default EXTERNAL!DATAPUBLISHER, so I am expecting openPDC to automatically publish new measurements. I have modified the EXTERNAL!DATAPUBLISHER parameters so no authentication is required. I launch my program based on the SubscriberTest from timeseriesframework and "happily" get the following messages:

"Attempting connection...
Attempting command channel connection to publisher...
Connection established.
Data subscriber command channel connection to publisher was established.
Initiating throttled unsynchronized subscription...
Success code received in response to server command "Subscribe": Client subscribed as compact unsynchronized with 0 signals.
Initiating locally synchronized subscription...
Success code received in response to server command "Subscribe": Client subscribed as compact unsynchronized with 0 signals.

No data received in 10.0 seconds, restarting connect cycle...

Connection to publisher was terminated, restarting connection cycle...
Data subscriber command channel connection to publisher was terminated."

FINAL QUESTION:

How can I receive the measurements ? I tried creating another DataPublisher Action Adapter from the openPDC Manager interface, but that did not change a thing. I am a student working on this project, so any help is highly appreciated.

Dec 6, 2012 at 1:34 PM

Hi alexandrun,

Have you modified the filter expression? The system won't know which measurements to send unless you specify them by defining your filter expression. The syntax is exactly the same as the syntax for the input measurement keys described at the following link.

http://openpdc.codeplex.com/wikipage?title=Connection%20Strings#input_and_output_syntax

Thanks,
Stephen 

Dec 6, 2012 at 2:10 PM

Hi Stephen,

Thank you so much for your prompt and kind reply! I have been stuck at this stage for a while. I finally get measurements, so the next step will be to "get my hands" on each one of them.

For other users/devs: I modified the filters to something like "FILTER ActiveMeasurements WHERE Device = 'PMU_ONE'" where PMU_ONE is the name of my device. This is how I managed to get the functionality I was interested in.

Best,

Alex