Hello! In the process of displaying the step number of a Sequential Function Chart (SFC) on a monitor, I sometimes encounter instances where the steps are quickly completed during a trip. In such cases, it becomes necessary to provide evidence to the customer regarding the completion of the specified path or to analyze the recent occurrences. My usual approach, using Schneider (Logix), involves utilizing an array named Steps with a size of 50 and a REAL variable called Current_Step. The last change is expected to be reflected in Steps[49], with subsequent changes moving towards Steps[48]. However, it appears that I may be overlooking something as the changes are not being detected and the numbers are not being displayed in the array. The logic involved in this process includes the use of NEG and MOV instructions in LD, within an AOI structure. While seasoned Structured Text (ST) programmers may find my methods amusing, it primarily serves as a troubleshooting tool. I am open to suggestions for a more efficient approach, as the current method involving concatenation in an Excel sheet was chosen for expediency. Thank you for your input.
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Hi there, it appears to me like your logic may be experiencing latency or is too slow to capture fast transitions. I'd recommend to try analyzing the recent occurrences in real-time and store the step number and timestamp of each step in an array rather than just capturing the last step number. This data logging approach will give you robust evidence of path completion and will be much more convenient for troubleshooting purposes. Take note that this approach might consume more memory but it would provide a more detailed historical record of your process. As for the Structured Text issue, don't be too hard on yourself. Even the best of us were beginners at one point. Keep learning and experimenting, it is the only proven way to mastery!
Hey there! Your approach using Logix seems pretty reasonable. However, it appears there might be a timing issue - if the steps are getting completed too quickly, the changes might not be captured in your array. Instead of an array, you could consider employing a First-in, First-out (FIFO) loading system which could be more efficient in capturing fast changes. Additionally, if you're logging data for customer review or troubleshooting, you may also want to consider time-stamping your data. This would give you a more precise playback of the steps and help pinpoint moments of interest. Finally, programming in Structured Text gives you the opportunity to keep track of changes in a more readable and understandable format - something both you and your customer might appreciate! Good luck with your project.
Hello! It seems like the steps are processing too quickly to be stored in the array and therefore not being reflected on the display. Consider updating your AOI to temporarily "pause" during each step and process the data so it captures the movement. You can use either a timer or a variable cyclical sequence to allow for this lag in the process. Also, check whether any steps are being skipped over due to your programming instructions. Lastly, keep your array size flexible for modification based on the quickness of steps. Leveraging these changes, you'll likely be able to provide a more compelling evidence to your customer, and your analysis could become more precise. Hope it helps!
It sounds like you're doing some interesting work with your SFC and trying to capture that execution data effectively! One thing to consider is whether your array is being updated properly within the AOI; you might want to add some debugging to ensure that the MOV operations are being executed as expected. Also, have you considered implementing a ring buffer instead of a linear array? It can help maintain a rolling history of the last few steps without worrying about the positions shifting as new steps occur. Lastly, if you're still facing hiccups, using structured text for clearer logic could provide a clearer pathway for troubleshooting and might even speed up detection of changes. Good luck!
It sounds like you're doing some interesting work with SFCs! One suggestion I have is to make sure that the triggers for updating your Steps array are firing correctly. You might want to check that the logic associated with your MOV and NEG instructions is being executed as intended, especially if you're using them within an AOI; sometimes, it's easy to miss a small condition that halts execution. Additionally, consider incorporating a timestamp or a sequential event counter alongside your step numbers to help with analysis and tracking. It might add some overhead, but it could provide a clearer picture during analysis. Good luck!
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Answer: 1. How can I efficiently display the step number of a Sequential Function Chart (SFC) on a monitor using Schneider (Logix)? - One efficient approach is to utilize an array named Steps with a size of 50 and a REAL variable called Current_Step. Ensure that the last change is reflected in Steps[49], with subsequent changes moving towards Steps[48].
Answer: - The issue may be related to the logic implemented within the AOI structure. Check for any errors or oversights in the implementation that may be causing the changes not to be detected and displayed.
Answer: - Consider enhancing the troubleshooting tool by exploring alternative methods for displaying step numbers more efficiently. Collaborate with other experienced programmers or seek suggestions for optimizing the current approach.
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