Implementation
Variable information is collected by a Programmable Logic Controller (PLC). The trender system is continuously reading data from PLC using OPC. This acquisition process lives in a server, and was implemented using WCF .NET in C#. The low level communication with PLC is directly done through a C++ COM Library OPC compliant, this library exposes C# friendly methods so it can be invoked and used in C# processes.
The client implements a WCF client that receives events from the server to show the charts.