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Joe Tauser

MVP 2017
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Everything posted by Joe Tauser

  1. No. No it's not. Saragani is one of the Creators. You take take his word on it. Send this issue to support@unitronics.com and see what they have to say. This sounds like more of an OS bug. Joe T.
  2. There's nothing in the Help on the DT Raw block, but it implies that the Data Tables are a contiguous chunk of memory. What you're describing kind of sounds like writing a 32 bit word to a 16 bit variable. Since you can't post your code, it's very difficult to troubleshoot the problem from descriptions only. There is probably something in your Modbus blocks that you mistyped or are overlooking. I suggest you contact Unitronics official support at support@unitronics.com. They will ask for your program, and hopefully you can send it to them. Joe T.
  3. I use these guys often in the US - https://www.autonics.com/product/category/2000013 Find something with the "T" or "V" output for 24 VDC. Joe T.
  4. There are no limitations on Data Table reads and writes - they are executed when they are called in the ladder code. If you have a lot of them then the scan time may be affected a bit, but it doesn't seem like this is the problem. It also sounds like you are hammering your Modbus transfers as fast as possible, which is where I would suspect the garbled data is coming from. There's supposed to be a checksum in the Modbus frame but you may be stomping on yourself. Have you tried inserting a time delay between Modbus operations? Will your process tolerate a 1/2 sec delay between tr
  5. @Isakovic- Because the -20 is not a two-wire transmitter. It's a powered device with two outputs - pH and conductivity. You have to zoom into the above diagram to see the rest of the story: The power supply negative is connected to the loop negatives. This is a sinking loop output and absolutely ridiculous. In your diagram, take the negative of your 24V power supply and connect it to the 0 on the HI 98143-20. You'll immediately see the problem. If we had isolated analog inputs this could be made to work. But, alas, we do not. Joe T.
  6. I'm guessing you've already seen this post- The -22 should work. The -20 won't. Joe T.
  7. UniStream can be programmed in ladder or C. It is not IEC 1131-3 compliant. Joe T.
  8. @rkager We're not Unitronics employees here. These are both functional changes to UniStream so copy your posts and send them to support@unitronics.com. Let us know what they say. Joe Tauser
  9. I did a little digging online on the STL language and it seems to be unique for each PLC. The Visilogic STL language is not in the Help file. You can't edit it, so it really doesn't matter. @ScottF - I am old to PLCs as well -🙂 AB T40 and Modicon P190 terminals as well as the GE Series 1 handheld. There's a lot of information in the Visilogic Help but STL is not one of the topics. I seriously doubt if it ever will be, as the Vision series is a mature product line and they're focusing their efforts on the UniStream series. Their Help writing department is very small. I
  10. The compiler has broken your logic into five separate statements. Here are some things to remember when looking at STL lists: ! = Start new logical statement LB = Local Bit - used as a scratchpad between statements So it translates to this order- 1. If MB 0 and not MB 258 and Rising Edge SB 16 then set local LB 0. 2. MB 1685 state = LB 1 (saves a copy for later) 3. If LB 0 then Reset MB 1685 and Reset TD 366 4. If SI 9 NEQ 80 AND LB 0 then store constant 80 into SI 9 5. If LB 0 and LB 1 then Load Last Display You'll have to de
  11. In UnitronicsLand, physical placement does not guarantee scan sequence. It's what the compiler decides to do, which is not always predictable. Right-click on the left side of the network and select STL Quick View to look at the compiled code sequence. You should be able to figure it out and this is how the network logic will solve. If you're worried about this I would break the logic into more than one network. Joe T.
  12. Now that's funny, in a PLC geekasoid way! 😄 I see a T-shirt here. Joe T.
  13. There's a Daylight Savings time program in the Examples. Note that this program requires the PLC to be powered up when it's time to change the clock. Joe T. Unistream_070_Daylight_saving_time.ulpr
  14. By "Allen Bradley PLC" I'm guessing you don't mean a PLC 5, a SLC 500, or a uLogix 1000. 1. You'll need to add a network. 2. Set each Unitronics as an Ethernet I/P Scanner (master) and you can write to the AB. Or set each Unitronics as an Adapter and the AB can be programmed to read from them. Either of these will "probably" work, but my experience with Ethernet I/P is if all communicating devices don't bear the AB logo then it's going to be glitchy. For Ethernet I/P - <rant> Scanner = Master Adapter = Slave I will continue to use this
  15. Post your program so we can see how you're handling Modbus. Joe T.
  16. This is actually not a trivial problem. It consists of three logical parts: 1. The primary TD timer (not hard) 2. The blinking lamp is achieved by two more timers - one for ON and one for OFF off the lamp. 3. Some math to examine the primary timer's preset vs accumulator %, decrease the OFF timer's preset, and increase the ON timer's preset. The sum of those two presets must equal the primary timer's preset. This is probably the easiest solution. If you want to take a swing at it and post your program we can probably help. Joe T.
  17. No easy out. The Data Table is the way to go. Joe T.
  18. The current date and time are bundled together in the SI registers so that a four digit number represents hours and minutes and/or month and day in a single number. You're going to have to do some math to strip them apart by dividing by 100 and then extracting the remainder out of SI 4. Post your program so we can have a look. Joe T.
  19. I would not continually force a value to the PID status register. The PID block should write that value all by itself to report what it's doing. Here's how I do PID- I also always make something on another screen to allow manual tuning- As far as manual tuning goes, I posted this a while back- Manual loop tuning 101: Start with Kp = 100 (10.0%) and Ki = 0. Then start lowering Kp until the process starts to just ring around the setpoint. If it overshoots wildly you need a bigger Kp. Measure the time between peaks. This is the natural c
  20. @t0r3r0s - please don't post the same problem in more than one place. Joe T.
  21. Is the screen totally blank? For starters, look in the Help under topic "bootstrap" on how to get the PLC into a mode where it will be more cooperative. A V280 is a standard PLC, as opposed to a V570 which is an enhanced unit. The suggestions here don't necessarily apply. The default baud rate for a V280 is 57600. Visilogic does not automatically try this baud rate, but relies on what the user sets it to. Joe T.
  22. No, there's not and you are definitely in the deep end of the pool. PCOM has become a legacy thing with the development of UniStream and I wouldn't expect any updated documentation to appear on the website. I looked over the PCOM document and the section on Data Tables is pretty short and ambiguous, as you have found. The fact that the newest PLC listed in it is a V280 is not encouraging. For your specific question, all Unitronics timers in a Vision are 0.01 timers with 32 bit values for the preset and accumulator. The HH:MM:SS.ss display is done in the software so us humans can under
  23. Do you have the wired Enable signal on the drive terminals connected (DI0)? Joe T.
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