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Showing content with the highest reputation since 09/19/2018 in all areas

  1. 2 points
    As a programmer, I spend a lot of time downloading a program to a PLC that was previously used for something else. There are many, many prompts that I must wade through to get the program downloaded, most with no audible notification. Can we please provide a "Yes To All" prompt at the beginning so that we can initiate a download and walk away for the lengthy download process?
  2. 2 points
    https://aviationhumor.net/the-us-standard-railroad-gauge-is-4-feet-8-5-inches/
  3. 1 point
    Give a look at the "num" to ASCII under the strings menu. You can set an indirect position for the decimal place on the HMI. It may help you achieve what you want.
  4. 1 point
    Unitronics is well aware of this "mistake". Everyone who has put MF values on a display has faced this problem in UntronicsLand. I've run into the problem with competitor's HMI products as well. The nature of a IEEE floating point value is you can't easily extract the location decimal point and the number of significant for display. True, you could theoretically create an object that could extrapolate the decimal via code. But then what would you do if the float became large or small enough that an exponent was required? What if the exponent needed to be negative? Anyway, the Vision series has never promoted itself as a floating point powerhouse - you can tell because there are only 64 of this memory type. Unitronics will not be improving this product line's functionality significantly - the focus is on UniStream now. I feel your pain on this and have banged my head against that wall. But the problem is still there. I would advise you to go back and revisit the algorithms using MI's or ML's, especially if displaying the output value is required. Joe T.
  5. 1 point
    I´m not sure if this fits your needs:
  6. 1 point
    This is a good topic for discussion. It's not a matter of technology, it's a matter of money. Approval Agency money. Specifically - in the US anything that is taken seriously must have a UL listing. The testing procedure cost jumps up significantly when you go above 50V. I have a customer that spent $30K to get a modification to a standard temperature controller UL listed. He was using a couple thousand a year so he could justify it. So- If Unitronics has an AC input Jazz PLC, how many would you buy? Most new products in any manufacturer's line are driven by an OEM request of a couple of thousand pieces. All the 24V switching power supplies I sell these days have a 90-264 VAC input voltage range. Most are less than $100 US. In the US a standard power supply is 480V, which is easy enough to step down to 120V as JohnR mentioned. You don't need more than 250 VA to power the PLC and the sensors with some 120V left over to drive contactors and solenoids. Considering that the control voltage is often routed outside the enclosure, which would you rather grab onto if a cable gets broken or worn? Joe T.
  7. 1 point
    Yes, go into INFO Mode and obtain (or set) the IP address of the PLC. Also note the PLC Name. Make sure your computer you are trying to connect with is on the same subnet as the PLC IP address, then use a crossover ethernet cable to connect. Do you need to know how to enter the needed details into VisiLogic?
  8. 1 point
    Glad you mentioned that Ausman. I was going to ask, and forgot, if the coil was always on or if he actually saw it turn on. I've been surprised on occasion at what coils are already set when I load software. It's usually a good idea to load a blank project and perform initialize & reset, prior to loading a new project in a PLC - even a brand-new PLC fresh from the factory.
  9. 1 point
  10. 1 point
    The real art to programming plcs is to first break down your process to every single procedure you are going to need to achieve your desired result, and then arranging those procedures to achieve this result in the most efficient manner. (You need to remember that in general plcs are very dumb and need to be told how to do everything.) I do this using a spreadsheet owing to the ease of moving things around, but there are many other methods including whiteboards, depending on complexity. (Some people end up with a correctly drawn flow chart once everything is finalised, but for me that isn't needed.) Once you have done that, if there is a procedure needed that you are unfamiliar with, or haven't used before, you then go to your plc's list of things it can do and find the function/maths/compare etc that best matches what you need to achieve. You then learn everything you can about the way it works, by consulting the help files, looking at examples and then physically doing a trial, using the plc, of something simple involving that procedure to ensure you are totally familiar with the way it works. Eventually you can tie it all together into a fully functioning, simple as possible program that the little men, women and gender neutral people (we are very PC on this forum!) running around inside the plc are quite happy to do over and over and over again without getting tired. In this case it is using different types of compare. Also, please pay attention to Joe's response. cheers, Aus
  11. 1 point
    I know you are all likely saying: "Here we go again!!" but check this one out! I recently got a little petrol/gas (for you Americanos) inverter genset as a backup for the bigger standby diesel. Just in case the diesel happened to die at the worst time, the little one would still run enough stuff to cover crucial bases. So I oiled and fuelled it, set it all up and test ran it fine, started on first pull, and it said everything was ok. Time for a real world test by making it actually power stuff. I had been in the workshop all day, and decided to try it on a row of the flouros in there as a good test. So I went around turning everything off before working the supply changeover switch. Checked again that everything was off, changed the switch, cranked up the gen and then flipped it's switch. Overload! Stop! Huh??? Check it all out and all seemed ok. Try again. Same thing. What? Wandered around the workshop again checking everything and discovered that I had missed the air compressor supply. I had used it two days ago and forgotten to turn it off. It hadn't run AT ALL during the entire 12 hours I had been in the workshop as I would have noticed it and muttered "you idiot" whilst turning it off. But sure enough the little gremlins that continually sit on my shoulder had arranged for all the tiny leaks to make it flip the pressure switch during the exact 5 seconds it took me to change the supply switch and start the gennie!! Fair dinkum! If you work it out time wise based on my being there for 12 hours, the odds come out at something like 1 in 8640 for the pressure switch to change during the exact 5 seconds I'm shifting onto the genset! Sadly....very, very sadly.....none of these exceptional coincidences seem to happen on the occasional time I buy a lottery ticket! But they do seem to continue to happen to me all the time, leading to lots of perplexing moments! cheers, Aus
  12. 1 point
    Hello, Thanks for posting! Starting from last version 1.24.56, the maximal length of the MQTT password had been extended to 255 characters. Is that enough for your Azure broker? You're right, but it is right now in process and this new feature will be available in next UniLogic version (very soon) Hope it will help! Rivka
  13. 1 point
    Perhaps the timeout and retries on the missing slave are upsetting whatever intervals you have set for the sequential reads from all the others. Carefully go through the total possible timing per read and ensure that you have allowed sufficient "overlap clearance". cheers, Aus
  14. 1 point
    Ah, the classic toggle coil conundrum. This is the first thing I teach in my PLC class and is a lot harder than it looks until you've seen it done. It takes a while to get a real feel for the way a PLC solves it's program and the power of bits. I'd highly recommend taking an hour or so with the Help file and going through each function in the first couple of menus - Boolean, Compare, Math, etc. It really helps to know what tools you have available and how they work. Joe T. plciolatches JT.vlp
  15. 1 point
    You can find the first empty row using the Data Tables Find function block and searching for an empty field based on your data table structure. Joe T.
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