Skip to main content

Single point to double point and double point to single point information

Single point to double point information

For this example of changing single point information to double point information 2 protocols are being used. For single point signals – Modbus RTU master and results are going to be returned as double point information to IEC 60870-5-104 slave protocol. Firstly, configuration for Devices sheet should look something like this:


Device field should indicate which physical port is used in WCC Lite for Modbus protocol. Host field should be IP address of computer from which monitoring is happening. Other parameters should be specified according to protocol specifications or solution needed. 

Signals tab should look similar to this:


For source device alias and source signal alias there should be 2 names specified and separated with space. That way IEC104 protocol will take information from both of these signals. Single point information is changed to double point information via source math expression. In this case if signal1 and signal2 are both have values of 0, result will also be 0. If both of these values are 1 result will be 3. If signal1 value is 1 and signal2 value is 0 result will be 2, if reversed – 1.

To test this case, VINCI simulation program and VINCI Expert could be used. Connect VINCI Expert with WCC Lite PORT2 and with computer via USB cable. Then open one VINCI program window and select IEC104 master, make sure all setting match Excel configuration. On another VINCI window select Modbus RTU slave and VINCI Expert port (usually the lowest possible). Upload Excel configuration to WCC Lite, run both simulations and make sure both protocols are connected. On Modbus slave tab create 2 tags witch matching settings (function, data type etc.). Change tag values accordingly and observe the results on the web and IEC104 master tab:









Double point to single point information

To change double point information to single point Devices sheet and protocols to be used will be the same as earlier. Signals sheet should look similar to this:


In this case Modbus master reads 2 information units at once. To simulate this case connect WCC Lite and VINCI Expert analogously to the first example, protocol connections on VINCI app should also stay the same. For this test, Modbus tags will be:



If Value box is checked, it means that this value is 1.  Change tag values accordingly and observe the results on the web and IEC104 master tab:










Double point to single point --> Download

Single point to double point --> Download