Sampled Value

In this video, we’ll walk through how to transmit Sampled Value packets using the Vebko test device. First, we connect to the device using the MAC Address and set the data acquisition rate to Fast.

Then, under the Time Synchronizer tab, we set the time synchronization protocol to PTP. Next, we go to the Sequencer room and open the Hardware Configuration window.

In the SV Setting tab, you can either load an SCL file related to the Sampled Value, or manually define a new stream. In this tutorial, we’ll go with the second method.

We click the Add Stream button to add a new stream, and then use the plus icon (+) in the first column to define the desired number of Attributes

In this test, we’ve added four Attributes—one configured as a voltage data and the other three as current data.

We link two of these data points to the output of the test device, and assign fixed values to the other two.

We then set the Sample Rate to 4 kHz and specify that each packet should contain only one ASDU.

The linked data is displayed under the Analog Output tab. In the Voltage Output Signal and Current Output Signal tables, you can assign each data point to the voltage or current outputs of the device—or define a Virtual output. After applying and confirming the settings, you’ll see that two outputs—one voltage and one current—appear in the Table View module.

The voltage data is linked to the Phase 1 voltage output of the device, while the current data is defined as a virtual output. To monitor the packets sent by the device, you can use Wireshark software

. Once the test starts, packets following the IEC 61850 Sampled Value protocol will be generated and visible in WiresharkAs you can see, based on the configuration, each ASDU contains four Data Attributes—two of them are set to fixed values, while the other two are dynamically changing.