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Flex727

MVP 2017
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Everything posted by Flex727

  1. All electronic equipment is subject to the vagaries of power supply and ambient electrical noise - sad fact of our lives. Still better than working in retail.
  2. I've seen a power glitch (or surge) change timers before. Not sure how to prevent it other than make sure the power source is as clean as possible.
  3. Flex727

    communication issues

    And you're definitely using a 6-wire cable? I think it needs to be a crossover cable, not a straight-through cable (not sure about that though).
  4. Flex727

    communication issues

    What connection chart?
  5. Flex727

    communication issues

    Also, this isn't clear to me, are you using the programming cable supplied by Unitronics?
  6. Flex727

    communication issues

    Do we know if that USB-to-Serial adapter is compatible with the M91? I have no experience with that adapter.
  7. I agree with Ausman - this is all very confusing. With the exception of the Standard Vision, V120, an MI will not hold a number large enough to drive the output to the maximum frequency in the spec.
  8. Flex727

    communication issues

    I normally communicate with 9600, N, 8, 1. Confirm that your M91 Com port setting exactly matches your PCs Com port setting. Confirm you are using the correct Com port on your PC by going into Device Manager. This leads me to believe you aren't understanding Com ports. The port number on your PC and the port number on your PLC are not related. You must use the correct one for each.
  9. I'm working on a UniStream project and I've got a simple question. In VisiLogic, an image could have a transparent background by checking the appropriate box in the image properties. When that box was checked every pixel in the image that was the same as the pixel in the upper left corner would assume the color of the background, thus rendering the parts of the image "transparent". I can't find a similar option in UniLogic. In the Help file, there is mention of something identified as "Background Color \ Image" which looks like it might apply, but that property is not present in my version of UniLogic (1.12.20) when I select the image. What am I missing?
  10. Flex727

    HMI input staying locked in logic

    Your typo confused me. The bottom line is that the bit assigned to the HMI button will not Reset if you have the button action assigned to reset on release but the button is hidden before it can be released. It would be helpful if you would be precise in your questions. There are lots of contact, coils, and HMI elements in your posts - and there's no such thing as a Positive Transition Coil. The statement above (starting with "The bottom line...") along with what I mentioned before that Positive Transition Contacts are energized for exactly one PLC cycle when the associated coil is energized should answer all your questions. The positive Transition Contact will be re-evaluated on every scan, but the requirement for being energized is a positive transition of the coil, therefore it must see the coil turn off, then back on again to be energized again for one PLC scan. If your question isn't answered yet, try to ask again in a different way and I'll try to help.
  11. And to just expand on what Ausman is saying. The actual physical output from the PLC is not altered until the complete ladder routine has finished executing. It is only the final state of the digital output coil that will be sent to the output module on each PLC scan. Also keep in mind that ladder code is not like other computer code. A direct coil that is not explicitly turned on is explicitly turned off. Understanding that last sentence is critical to understanding the difference between ladder logic and regular computer programming.
  12. Do you have 24 VDC connected to the Snap-In module? Do you have the jumpers set properly? Do you have it wired like this:
  13. Flex727

    HMI input staying locked in logic

    Yes, if the button goes away, you can't unpress (release) it! If you insist on hiding the button when pressed, then reset the coil in ladder logic. I don't see "N2_HMI_READY" in your post, so I don't know.
  14. Flex727

    HMI input staying locked in logic

    You're conflating coils and contacts. A coil is what you use to change the status of a binary memory bit (0 or 1), a contact is what you use to perform an action based on the status of that bit. (apologies if you already know this but your comment indicated to me that you might be confused on this point) "Setting" a coil is the same as latching it. It will stay on until it is unlatched (Reset). A positive transition contact will pass logic power flow for one PLC cycle when the the coil is energized (whether by direct or latching). That positive transition contact will not ever pass logic power again unless the coil turns off then on again. It absolutely does (if you coded the button correctly), but with a direct contact instead of a positive transition contact, it can execute many times (maybe hundreds of times) before the reset occurs because of the time it takes to remove your finger from the button. No, absolutely not. Yes, correct. I don't know what you're asking here.
  15. Flex727

    HMI input staying locked in logic

    You MUST use a positive transition contact for "HMI_START_N2_PURGE".
  16. I'm not sure I understand exactly what you're trying to do, but if you want to alternate engines every 2 hours of operation, I would assign a coil to determine currently active engine (0=Engine 1, 1=Engine 2), then toggle the coil triggered by your accumulating register. Place the inverted contact for that coil in series with MB0 and direct contact in series with MB1.
  17. @Ausman's cleverness never ceases to amaze me!
  18. I think that's why they added that feature to the UniStream product line.
  19. Yes, re-wire that speaker to a computer. In all seriousness, I sincerely doubt it, but I eagerly await the response from someone who actually knows something.
  20. It says V120, not V1210 in that help entry you're referencing. I think the V120 is an older Vision model, not Enhanced Vision. Have you tried it to see if perhaps it outputs the PWM in units of 1 Hz instead of 0.1 Hz? @Cara Bereck Levy, does the Help file need to be updated for this function?
  21. One way is to store the RTC as strings in a couple of MI vectors. You can then copy those into a data table or simply display them on the screen, triggered by the reset button.
  22. I didn't notice that. Great spot!
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