Connecting Excel to Control. Logix PLCdevby John Schop. Have you ever lost data in a CLX processor, because you downloaded new codeUnfortunately, when you donwload a program to a Control. Logix processor, you also download the values of the tags variables. A solution to this problem that could be useful, is an Excel sheet that reads and writes values to the Control. Logix processor using the DDEOPC capabilities of RSLinx. In this article, I will show you how to create one of these sheets for your projects. Heres what youll need Microsoft Excel, with some basic knowledge about programming macros in Visual Basic RSLinx not the Lite version, because that does not have DDEOPC capabilities A Control. Logix processor of course. Lets fire up RSLogix first, and create a bunch of tags with values. In this example, I created 2 arrays, of the types DINT and REAL, each with a length of 1. These arrays I filled with some values Im not going to do anything with the PLC program, I just need some data in a number of tags. Next, were going to set up a DDEOPC Topic in RSLinx. Depending on the version of RSLinx you use, it might look slightly different, but you should be able to follw this with the screenshots. Assuming that you know how to setup RSLinx initally to get online with your controller, Ive skipped some steps. The setup I use looks like this in RSLinx As you can see, I have a 1. CLX rack, with a 1. ENBT card in slot 1 address 1. The one in slot 2 is the processor we are going to use for this exercise. Now, open up the DDEOPC topic configuration by clicking DDEOPC and then Topic Configuration in the top menu of RSLinx. Peachtree Accounting 2003 Download here. Im going to create a new DDEOPC topic called EXCELTEST, and use the Logix. In order to do this, you have to click the New button, give the topic the desired name, and make sure the processor in slot 2 is selected as the source before you click DoneTo test if your setup is working, at this point you can use the OPC test client provided with RSLinx. Im not going into detail about that, but I did make sure this worked before continuing with the next step, creating the Excel sheet. Lets start up good old Excel, and create a new workbook. On this workbook, place a new command button. You can find the Command Button control in the Control Toolbox toolbar in Excel. When you have the button, right click on it and choose View Code. This will take you to the Visual Basic Editor First, create a function that will open the DDE topic to Excel Now, if I call this function from the Command. Allen Bradley Micrologix 1500 Software' title='Allen Bradley Micrologix 1500 Software' />Button. Click event, it will open the link to RSLinx The variable rslinx will hold the number of the open channel. All subsequent DDE functions use this number to specify the channel. To save you all the steps to program the rest of the code, here is the final code to get the array of REALs out of the controller, and put them in cells D2 D1. DINTs in cells E2 E1. Now we know how to read, it would of course be a lot of fun if we could write values as well. I would like to be able to change the values in the cells, and then hit a Write Data button. First, make another button on the sheet mine looks like below nowAnd then write some code for the button The way this is implemented is of course very rudimentary, but once you get the concept, the sky is the limit. To make this easier on everybody, Ive included the Excel file with the code already in it. The only thing you have to do to make this Excel sheet work, is make sure there is an DDEOPC topic in your RSLinx setup called EXCELTEST, and the arrays REALArray and DINTArray in your controller of at least length 1. Welcome to the PLCS. File Manager LoginRegister You must loginregister to be able to upload a file Click on the to download. Allen Bradley Micrologix 1500 Software' title='Allen Bradley Micrologix 1500 Software' />Georges Creek Wastewater Treatment Plant Allegany County, MD. PLC based control, instrumentation and SCADA system. The system included Modicon PLCs, Square D. RSLogix 500 Now Available on MrPLC. Hard Drive Light Stays On Vista. Many people are surprised to learn that AllenBradley has a version of RSLogix 500 programming software that. Method to connect a ControlLogix PLC to Excel for reading and writing tag values. When it comes to PLC training courses, we are a leading provider of courses within the UK Ireland. Our PLC and HMI training covers the following manuafcturers and.