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About Mr.Sovereign

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  1. Hmm, I am looking more into how this works and the button in the DCS executes script to log into the PLC server the username/password are set automatically. Once this account logs in on the PLC server Windows Task Scheduler executes a .bat file which opens the .mer file. So, all the DCS does is log the user in, the PLC server does the rest. Once the HMI is open, the operator has to be able to log into the PLC in order to navigate the pages, but I don't want them being able to control from those pages. The equipment should only be controlled in the field.  I'm not sure if this is possible, with them having to login at the HMI interface. Would I run into the same issue using VNC? The alternative is to remove the access all together.   Thanks
  2. Hello, On our DCS we have a button that will open an RDP connection to our PLC server and open the .mer file connecting the DCS to the PanelView HMI. This is supposed to be used for troubleshooting purposes only, but that is not the case. Is there a way to prevent operators from operating the HMI through the RDP while still allowing them to have read only access?   Thanks, Michael
  3. PLC Programming Language

    Oh beginner tip from a beginner, though you are likely aware ... leave detailed notes about your code, I'm struggling through a poorly documented PLC program right now lol.
  4. PLC Programming Language

    Ladder is foundational for PLC's. If practical I would write all programs on a PLC in ladder. I am an electrician who recently started programming mostly in FBD on a DCS. The more languages you know the more transferable your skills in the future. I would learn LD, FBD, then ST...since you understand syntax if you need to learn ST it will be fast. FBD has a bit of a learning curve to it and I see it used in PLC's more often then ST (in my limited experience). Just my suggestion. 
  5. I'm fairly new at this but what I've seen is under the Logic dropdown > MAP PLC/SLC Messages. If there is data there attached to a file number, then in DeltaV the messaging class was Class 3 with PCCC. One of our other PLC programs one of the routines in the tree handles DCS Comms. A MOV block takes information from a transmitter and moves the value to a tag in an array in controller tags. in the DCS the dataset is configured as UCMM with Logix Tags and the Logix tag name is used matching the tag name in the PLC array.  With other parameters in the dataset the PLC is able to send the value to the DCS. (Rack#, slot#, data type.) For example the tag name in the PLC could be _TX_DCS_FI-1234 and this tag name would be used in the DCS. Another one similar to the first has controller based tags for DCS comms and MAP PLC/SLC with a file#. ST is used in the PLC to write to the controller tag array. Class 3 with PCCC is used in DCS. For example the PLC could have an INT array tag called _TX_DCS with 50 elements in the array. each element corresponds to a sensor or signal. the file number in the MAP PLC/SLC could be 11. but if you have 50 elements in the PLC array then you would want to grab 50 values in the DCS, and these would be made into signals under the data set. I had to set up a dataset on a new Logix 500 controller. This was trial and error with data types, file type, and file number. I managed to get data from file number 7 which comes from integers and made it a 8bit unsigned integer. I couldn't spend more time on it to figure out how I got it to work, but it does. Maybe I will revisit it to learn. If you saying that its explicit messaging, I know there is Class 3 explicit, where my examples are Class 3 with PCCC. But, hopefully I have given you something useful to work from.