We will use scripting and the control function " ChangeConnection" to switch the connection when a loss of communication is detected. The first will be a dynamic connection, capable of pointing to either processor in the redundant pair. What we will do, in order to provide automatic fail-over, is create three primary connections. This is the connection that will be used for all tags used for visualization and control on the HMI.
![paquete wincc para step 7 5.6 paquete wincc para step 7 5.6](https://http2.mlstatic.com/D_NQ_NP_790601-MLM20346720268_072015-F.jpg)
I've renamed this Connection to "CPU_400H" and this will be the connection that we configure to switch been CPU's (failover). If you open up the Connections Editor from the HMI Project (in the Project Tree) you will see that a connection has automatically been created for you. Open up the hardware configuration (network view) and add an HMI connection from your Proxy Station to the Comfort Panel.
![paquete wincc para step 7 5.6 paquete wincc para step 7 5.6](https://practinet.mx/wp-content/uploads/2021/06/plcduinoserial2-768x432.jpg)
Step 3: Create a Connection to the PLC Station But you can do the same with an Advanced Runtime application. To do so, choose "Add a New Device", select the type as "Controller" and pick "Device Proxy."Īfter the new station has been added to the Project, right click the station in the project tree (or from Device View) and choose "Initialize Device Proxy." Navigate to and select your Step7 v5.5 project and it will open a new dialog to allow you to choose which source device and what data you would like to add to your Proxy Station.įor the purpose of this demo, I will add a Comfort Panel to my project. TIA Portal does not support programming of the 400H inside the Portal, but you can easily import a station from a Step7 v5.5 project into Portal to make things easier. Step 1: Import your 400H system into TIA Portal Yet for anyone who already found this blog, I'll walk you through configuring WinCC Advanced or WinCC Comfort to work with a redundant pair of S7-400H CPUs and automatically handle connection failover. Nothing I'm sharing below is secret, you can easily read the information from this link. Luckily, Siemens provides a great Application Example to make the process easier. But for now, programming of the 400H system is completed in Step 7 v5.5, the station must be imported into Portal as a Proxy, and any connection fail-over must be manually added. Hopefully, when the S7-1500H is released, this functionality will be added as well.
![paquete wincc para step 7 5.6 paquete wincc para step 7 5.6](https://i1.wp.com/filecr.com/wp-content/uploads/2019/12/Simatic-TIA-Portal-Free-Download.jpg)
If you've worked with TIA Portal and the 400H CPUs in the past, you probably know that Portal does not have any automatic fail-over mechanisms built in for WinCC Advanced or WinCC Comfort. Today I'd like to share one of these examples that I've relied upon several times when working with the S7-400H and programming HMI's in WinCC Advanced or WinCC Comfort configuring automatic connection fail-over. Over the years, I've built up a personal library of links and documents that I reference whenever I come back to an issue that I know I've seen before and have forgotten how we fixed it in the past. Oftentimes, I will find those settings and tricks in a great blog, application example or help file. In the words of my wise colleague Lillian Walker, "The redundant thing about redundancy is that I have to read all of the documentation twice." Oh, so true. Sometimes those small details are hard to catch. You find that there are many small settings and 'tricks' that you uncover while setting up redundancy, redundant Modbus communication, redundant communication interfaces for I/O, configuring hardware, etc., that you need to get things running. For anyone who has spent much time working with the SIMATIC S7-400H, it becomes quickly apparent that the devil is often in the details.