PLCcom for S7
Symbolic S7 Access for .net and java Developers

The PLCcom for S7 library is a highly optimized component specially designed for java and .net software developers, which has been created 100% under .net or java. The component enables developers under the programming platforms .net or java a comfortable and program-controlled access to S7 PLC data.

Depending on the control unit, access is via

  • Put/Get or
  • symbolically using legacy access to older controllers
  • or symbolic access via Secure Communication (TLS encrypted) on newer generation devices.

PLCcom for S7 is compatible with S7 controllers (200, 300, 400, 1200, 1500 series, ET200SP, SoftSPS WinAC RTX, and Logo! 0BA7, 0BA8 0BA0, 0BA1, 0BA2, as well as CPUs from other manufacturers (e.g., VIPA 100V/200V/300V/300S, etc.).

The libraries support the protocols Profinet, MPI and PPI (see data sheet)

The component is certified in accordance with the requirements of the Cyber Resilience Act (EU 2024/2847) – CRA for short.
You can find the relevant certificates on the download page.

PLCcom for S7 is available for two programming platforms:

    1. .net-Version
      The .net version supports both the classic .net Framework-programming from Framework Version 4.7.2 als auch modernere Frameworks bis hin zu .net 10.0.
      The delivery package contains libraries for the classic .net Framework versions 4.7.2 and 4.8. There are also versions for .net-Standard Version 2.1 and versions for .net 5.0, .net 6.0, .net 7.0, .net 8.0, .net 9.0 , .net 10.0 in the delivery package.
      PLCcom for S7 (.net version) is provided via a Nuget package.
    2. java-Version
      The java version provides developers with a library that can be seamlessly integrated into java-based applications and is compatible with common development environments such as Eclipse or NetBeans. It supports java JRE / OpenJRE from Version 11.23 and has been tested up to Version 25 .
      PLCcom for S7 (java version) is provided via Maven Central Repository.

PLCcom for S7 delivers high performance

PLC communication is never “free”: no matter which protocol you use, every access creates communication and processing overhead on the PLC and can impact PLC cycle time at high polling rates.
During development, great care was taken to ensure that all components and algorithms execute as efficiently as possible.
Smart optimizations in the library reduce communication overhead — which lowers PLC load and keeps cycle times stable.

  • Accesses are efficiently bundled instead of being transferred individually.
  • Reduced number of telegrams for frequent polling.
  • Optional parallelization when maximum data rate is required.

The result: maximum data rate with minimal PLC load — ideal for HMI/SCADA systems, data logging, and any application that reads many variables at short intervals.

For a quick start, you’ll find runnable example projects for .NET and Java in our GitHub-Repositories.

Below are two simple code examples to illustrate this:

            // Create a device instance
            Tls13Device tlsDevice = new Tls13Device("192.168.1.100");

            //connect
            ConnectResult connectResult = tlsDevice.Connect();

            // Which variables do you want to read?
            ReadSymbolicRequest readRequest = new ReadSymbolicRequest();
            readRequest.AddFullVariableName("DataBlock_1.ByteValue");
            readRequest.AddFullVariableName("DataBlock_1.RealValue");

            // Read from device
            var readResult = tlsDevice.ReadData(readRequest);

            // Evaluate results
            if (readResult.Quality == OperationResult.eQuality.GOOD)
            {
                foreach (PlcCoreVariable variable in readResult.Variables)
                {
                    Console.WriteLine($"{variable.VariableDetails.FullVariableName} Value: {variable.Value}");
                }
            }
            else
            {
                Console.WriteLine($"Read not successfull! Message: {readResult.Message}");
            }


            ' Create a device instance
            Dim tlsDevice As New Tls13Device("192.168.1.100")

            ' connect
            Dim connectResult As ConnectResult = tlsDevice.Connect()


            ' Which variables do you want to read?
            Dim readRequest As New ReadSymbolicRequest()
            readRequest.AddFullVariableName("DataBlock_1.ByteValue")
            readRequest.AddFullVariableName("DataBlock_1.RealValue")

            ' Read from device
            Dim readResult = tlsDevice.ReadData(readRequest)

            ' Evaluate results
            If readResult.Quality = OperationResult.eQuality.GOOD Then
                For Each variable As PlcCoreVariable In readResult.Variables
                    Console.WriteLine($"{variable.VariableDetails.FullVariableName} Value: {variable.Value}")
                Next
            Else
                Console.WriteLine($"Read not successfull! Message: {readResult.Message}")
            End If

			
		//create a device instance
		Tls13Device tlsDevice = new Tls13Device("192.168.1.10");

		// connect
		ConnectResult connectResult = tlsDevice.connect();

		//which variables do you want to read?
		ReadSymbolicRequest readRequest = new ReadSymbolicRequest();
		readRequest.addFullVariableName("Datenbaustein_1.ByteValue");
		readRequest.addFullVariableName("Datenbaustein_1.RealValue");

		// read from device
		var readResult = tlsDevice.readData(readRequest);

		// evaluate results
		if (readResult.getQuality() == OperationResult.eQuality.GOOD) {
			for (PlcCoreVariable variable : readResult.getVariables()) {
				System.out.println(variable.getVariableDetails().getFullVariableName() + " Value: " + variable.getValue());
			}
		} else {
			System.out.println("read not successfull! Message: " + readResult.getMessage());
		}

Example: simple reading with symbolic access

            // Create a device instance
            Tls13Device tlsDevice = new Tls13Device("192.168.1.100");

            // connect
            ConnectResult connectResult = tlsDevice.Connect();

            // Create a list of variable to write
            List writeVariables = new List();

            /*
             * IMPORTANT TODO FOR YOU!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
             * Before you can write, you need the imported variable. Either you have
             * determined it by a read operation or you have PLCCom output the empty
             * variable (without values)
             */
            var variableBody = tlsDevice.GetEmptyVariableBody("DataBlock_1.ByteValue");

            // Set the value and add the variable to the write list
            variableBody.Value = 1;
            writeVariables.Add(variableBody);
            
            variableBody = tlsDevice.GetEmptyVariableBody("DataBlock_1.RealValue");

            // Set the value and add the variable to the write list
            variableBody.Value = 123.456f;
            writeVariables.Add(variableBody);

            // create a write request
            WriteSymbolicRequest writeRequest = new WriteSymbolicRequest(writeVariables);

            // write to device
            var writeResult = tlsDevice.WriteData(writeRequest);

            // evaluate results
            if (writeResult.Quality == OperationResult.eQuality.GOOD)
                Console.WriteLine("write successfull!");
            else
                Console.WriteLine("write not successfull! Message: " + writeResult.Message);


            ' Create a device instance
            Dim tlsDevice As New Tls13Device("192.168.1.100")

            ' Connect
            Dim connectResult As ConnectResult = tlsDevice.Connect()

            Dim writeVariables As New List(Of PlcCoreVariable)()

            ' IMPORTANT TODO FOR YOU!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
            ' Before you can write, you need the imported variable. Either you have
            ' determined it by a read operation or you have PLCCom output the empty
            ' variable (without values)
            Dim variableBody = tlsDevice.GetEmptyVariableBody("DataBlock_1.ByteValue")

            ' Set the value and add the variable to the write list
            variableBody.Value = 1
            writeVariables.Add(variableBody)

            variableBody = tlsDevice.GetEmptyVariableBody("DataBlock_1.RealValue")
            variableBody.Value = 123.456F
            writeVariables.Add(variableBody)

            ' create a write request
            Dim writeRequest As New WriteSymbolicRequest(writeVariables)

            ' write to device
            Console.WriteLine("begin write...")
            Dim writeResult = tlsDevice.WriteData(writeRequest)

            ' evaluate results
            If writeResult.Quality = OperationResult.eQuality.GOOD Then
                Console.WriteLine("write successfull!")
            Else
                Console.WriteLine("write not successfull! Message: " & writeResult.Message)
            End If



		//create a new device instance
		Tls13Device tlsDevice = new Tls13Device("192.168.1.100");

		// connect
		ConnectResult connectResult = tlsDevice.connect();

		// create a list of variables for writing
		List writeVariables = new ArrayList();

		/*
		* Before you can write, you need the imported variable. Either you have
		* determined it by a read operation or you have PLCCom output the empty
		* variable (without values)
		*/
		var variableBody = tlsDevice.getEmptyVariableBody("Datenbaustein_1.ByteValue");
		// Set the value and add the variable to the write list
		variableBody.setValue(1);
		writeVariables.add(variableBody);

		variableBody = tlsDevice.getEmptyVariableBody("Datenbaustein_1.RealValue");
		// Set the value and add the variable to the write list
		variableBody.setValue(123.456f);
		writeVariables.add(variableBody);

		// create a write request
		WriteSymbolicRequest writeRequest = new WriteSymbolicRequest(writeVariables);

		// write to device
		var writeResult = tlsDevice.writeData(writeRequest);

		// evaluate results
		if (writeResult.getQuality() == OperationResult.eQuality.GOOD)
			System.out.println("write successfull!");
		else 
			System.out.println("write not successfull! Message: " + writeResult.getMessage());

Example: simple writing with symbolic access

Further extensive code examples can be found in the download package or here on the example page:

Guaranteed fast support - because your time is valuable

Industrial customers know this: Any downtime means production losses and enormous costs. With PLCcom for S7 , you not only secure a powerful communication interface, but also an all-round carefree package:

  • 1 year top-level support: With us, you receive exclusive support for one year. Should unexpected problems arise, our experienced support team will be on hand immediately to reduce downtime to a minimum.
  • 1 year maintenance plan: During this period, we guarantee you regular updates, upgrades and continuous improvements. This ensures that your software is always up to date.

The period can be extended on request. There is no automatic extension.

Test app for “PLCcom for S7” available for download (freeware)

The test app for PLCcom for S7 is now available for download. .net and java developers can use it to test absolute or symbolic S7 access to S7 controllers in advance.
The source code of the app is also included in the download package of the library.

Please visit our download section to download the app.

picture Plccom for S7 testApp

Ready to give PLCcom a try?

The best and quickest way to get to know our PLCcom component is to download the free trial version and get to know and try out the functions at your leisure.

You get full access to all functions and can start creating your software in no time at all.

Support Information

Changelog

Documentations

License Agreement

EU Compliance (CRA)

Cyber Resilience Act (EU 2024/2847)

Data Sheet