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Everything posted by stembera

  1. Hello World, some time ago I wrote a small application for ammonia storage in chemical factory. Just some measurements, valves and communication to SCADA system. One day, the guys from the factory asked me to perform a routine check of the system. OK, I arrived to site and had a call with control room about the tests. One of the prescribed tests was simulating overpressure in the storage and checking if the alarm is sent to control room properly. The emergency valves were electrically disconnected to prevent leakage of the ammonia. Everything went smoothly, alarm was raised, the control room confirmed alarm so I switched back to real measurement, when... What the hell? I hear sirens. I just ran out from the equipment room and I saw four red emergency trucks arriving in front of the room. Something went terribly wrong. Maybe the electrician guys disconnected the wrong valves and ammonia leaked due to simulated alarm? My world went black. Emergency situation in the town, probably I will be fired from the company. I found the leader of the emergency group and I shouted at him: "It was my fault, how dangerous is the contamination?" The guy replied: "What contamination? We were just asked for a presentation for local TV." Damn, I will never forget that day.
  2. Hello world, for update of my old project in Hydro Power Industry I downloaded a new version of DataXport (3.1.23) On this version, I am not able to establish connection with PLC via Ethernet. The only fix of the problem was to restore Windows to previous state and install an older version of DataXport (3.1.19). Do you have similar experience? Do anybody use the new version of DataXport on W10 and Ethernet connection? (Lenovo IdeaCentre Q180 PC w. W10 Home build 1507 (updates were not allowed due to metered 3G connection)) Thanks, Michal.
  3. In case of problems with serial ports, it is often useful to try to download program when PLC is STOPPED (you can do it from INFO mode). If you are in troubles with COM port init, try to load "Last known good" version of your software from SD card. It helped me sometimes.
  4. Dear Fotonic, If you are using Vision OPLC with B&W display, you can use "Moving image" dynamic object. Such object can move between two positions accordingly of variable value. If you are very patient, you can use freehand drawing on display with functions "Draw pixel", "Draw Line", "Clear Rectangle" from the Function Blocks menu. (Utils/HMI)
  5. Thank you Ausman for the idea. I will try Remote Access when the problem appears again. I will give you a feedback.
  6. Hello Arnor! Do you observe this behavior directly on display of PLC or via the Remote Operator? I have the same problem with V1040 when connecting via Remote Operator. Please see my post in the Remote Operator section (trend object only partly visible). I hope we will find the solution. regards, Michal.
  7. Hello world, connected to a remote PLC via Remote Operator, the object "trend" is often not displayed correctly. Only a part of the curves on the right side of the object are visible. Left part is invisible and can be displayed only by clicking the "M" button. Did you observe similar behavior of the trend object? Is it possible to get rid of this phenomenon? Thanks, Michal.
  8. Dear Juan, unfortunately the answer is no; Prepare PLC Side modem and Initialize PC side modem are different things. "Prepare PLC side modem" is intended for modem which will be located on the remote site via OPLC serial port. Initialize PC side modem is a AT command batch intended for modem which will be connected to PC for remote connection via peer-to-peer modem connection. Almost obsolete today. The first error could come from the three pipe signs before the command. Try to delete them and start initialization again. The next errors come from GPRS related commands, maybe your SIM card or your operator does not support GPRS. If you want to send/receive SMS only, erase all the GPRS-related commands and try to init modem again.
  9. This feature is not only annoying but it can also bring a fun to our lives. A year ago I finished work on some project connected through TCP/IP and I opened another one. Unfortunately, I forgot that the connection is not saved with project so when I started to watch process online, I saw very strange things. I was connected to the PLC which was not located in my office but in another country .
  10. Hello Steve, as Ausman said, cameras often have its own cloud technology which is bridging your router NAT (like Skype or TeamViewer). Maybe it is your case because there is not NAT record for camera system on your router screenshot. Are you sure your router has an public IPv4 address? Check this on WAN status page of your router. It should have true public WAN address (it must not be like 10.x.y.z or 192.168.y.z or 172.x.y.z). If on doubt, try to ping to your router WAN address from somewhere outside of your LAN. Does Ping work? If not, run tracert command from your LAN to some well known public address in the internet. (e.g. Google DNS The tracert record should show only one jump from LAN to WAN and it must go through your router as the only gateway between LAN and WAN. 3g / 4g routers have very often only LAN address as they are part of the wireless LAN of the nearest BTS. In that case you will need to ask your provider for public WAN address or you will have to use another service (TeamViewer). regards, Michal.
  11. Hi Steve, maybe firewall problem? Michal.
  12. Dear Sas, if you have two machines connected to one gateway, things are getting little more complicated. Because your router does not know which PLC you like to connect to, you must distinct them by using different TCP ports. You can use port 20256 for the first PLC and 20257 for the second one. Be sure these ports are properly initialized by Socket Init FB on appropriate PLCs. Next task, make your router to divert call from WAN on port 20256 to the first PLC and call from WAN on port 20257 to the second PLC. You can use next screenshot from my router as an idea (Private IP should be replaced with your LAN address of the first PLC; then do the same for 20257 and second PLC LAN address as well). If you have these jobs done, you can use your Remote Operator from the smartphone. Use the public WAN address of the router on port 20256 for the first PLC and the same WAN address on port 20257 for the second one.
  13. Dear Juha, 1. Be sure if you have properly initialized your modem with the init strings which belongs to Cinterion BGS2T. These strings should match both for PC initialization (Init PLC modem) and for the Modem Init block in your Ladder logic. 2. If positive, try to remove commands from the Init FB line per line until the Init FB returns OK. In that moment you have determined which command returns ERROR response. Find the AT reference manual for that modem and check what exactly that command does. In some cases you can omit some commands without lack of functionality. Good luck! Michal.
  14. Dear Vitor, yes, the examples work, indeed. I use this scheme regurarly. If you are on doubt, it is better to break the task into steps: 1. Is your modem properly engaged in cellular network? Modem should be initialized first, MODEM INIT should return Modem status (SI80/82/84, regarding to COM port number) =2, Error code (SI81/83/85) should return 0. If you are using a Check Signal Quality block, Signal quality should be > 0. 2. Is it possible to send SMS? Create some testing event triggered e.g. from the button on display, put your cell number to appropriate field in the SMS SEND block and observe if the block returns no error. 3. Create some SMS to SCAN in the SMS Config block, put the SCAN SMS somewhere to your ladder to be called every scan. Observe if the scan bit is going high after receiving the message. Also check if Last received phone number is exactly your number. You can use the Memory tab in the Output window or just have a look to the hexadecimal numbers in the Last Received buffer (e.g. 12 will be represented as "3231 HEX". If you change your testing code, it is better to restart OPLC to make the modem to be re-initialized. My advice: It is better to use telephone numbers in the international format. If everything above works, join all the pieces together. It should work. Good Luck!
  15. Hello world! I have a problem with HMI display element "Binary text"; it has often (not always!) pink border. This flaw occurs when the element has style "3D pressed", color ON = Green, Color OFF = Gray and Toggle is enabled. It is probably some mistake of display itself because using Remote Operator that display looks normally. I saw this fenomenon on various Enhanced OPLC displays (V1040 / V1210). Do somebody has the same experience? Is there any possibility to get rid of this? Thank you, Michal.
  16. On my first Unitronics training we were told to NEVER use long hold buttons or combinations of more buttons in one time. The reason was to ensure compatibility between displays and Remote Access / Remote Operator. Let us play with the cards we have got. If you need to avoid unwanted click, it is better to use sequential combination of two buttons. First button ("Action") is permanently visible and active. The second one ("Confirm") is visible and active only for three seconds after clicking of the first one. When operator needs the protected function, he clicks "Action" button. The "Confirm" button appears for next three seconds, the Action button goes to disabled state. The protected funcion is activated only if the Confirm button is pressed in the time when it is visible. After three seconds the Confirm button disappears again and the Action button returns to active state.
  17. Dear MTaha, I have bought one VirtualPLC license some years ago. My experience was not very good. Yes, it can simulate very easy programs. On the other side, when you start to test anything more complex, you will find that most of the Functions Blocks are not supported. And the even more annoying thing – every "download" to virtual PLC takes much more time than a download to real PLC! I had an idea to work in the hotel after returning from the site but it was almost impossible. Maybe they fixed the "unsupported FB" bugs but I keep to be very skeptical. Do anybody else some experience with that software? Regards, Michal.
  18. Dear guys, I know this is a little bit old thread but I cannot resist: Every dividing in the PLC world is very risky operation, regardless if you are dividing integers or float. For totalizers (in my case, to count generator power to kWh) I use another solution: 1. Add the value (power in kW, MI0) every second to the MI, let's say to MI100 (energy in kilowattseconds) 2. Make a test if this MI100 >= 3600 (because 3600 kWs == 1 kHh). 3. If it is not greater, do nothing. 4. If MI100 >= 3600, increment kWh counter (for example MI101) and MI100 = MI100 - 3600. 5. Go to back to step 1 .
  19. Don, try to play with System Integers SI103...SI110. Probably you have set them to 0, i.e. OPLC will keep the dead connection for infinite time. If you put some meaningful value to Socket TCP keep alive and TCP keep connection (something between 100 and 600 is suitable), the dead connection will be closed by OPLC and Remote Operator can open them again.
  20. If I can recommend, there is a nice example of High Speed frequency meter in VisiLogic under menu: Help --> Examples --> Version 900 --> Project Examples --> HSC_HSO --> Frequency Precise meter. Program is written for V570 but it will work for V430 also (some changes in hardware config required). Good Luck!
  21. For these tasks, a reliable modbus simulator for PC is absolute priceless thing. If you are in doubts, the first task is to check the setting with simulator. It is much easier to find problems if you can change the communication parameters interactively "on the fly" without changing, compiling and reloading PLC program. When the device communicates with PC without bugs, then it is the right time to start comunicate from PLC. Good luck, Michal.
  22. Thank you very much for your ideas. I will check them, I hope my generators will be happy. Michal.
  23. Dear lady and gentlemen, thank you for the explanation. Yes, I referred the Unitronics_library.zip . Now I see, it is gone. OK, I downloaded all the single pdf files from the web page. No problem.
  24. Thank you Ofir for your response. Yes, I know the structs attached to the UID0808THS module. Unfortunately, it does not solve my problem perfectly. Frequency of pulses from the speedmeter is ~100 Hz. If I choose measurement interval = 1000 ms, I will get frequency 99 Hz, 100 Hz or 101 Hz depending on count of pulses in the last second. For higher precision I need to choose longer time interval but I will lose change of speed in time. This is hardly usable for controlling of synchronous generator – it has to be kept between 49.9 Hz and 50.1 Hz (for 50 Hz grid). During startup and shutdown of generator exact ramp should be kept so I need to get nearly continuous speed measurement. There is HSC->Frequency FB in VisiLogic which perfectly meets my requirements; I was looking for something similar (or even better!) in UniLogic but without success. Maybe there is some chance to use hardware hack with PWM output hardwired to high speed input. Then I can count PWM pulses during 100 pulses from speedmeter. With some math I can get reasonable output but I am not sure if this is a way (at least I will need 1 extra input and 1 output). If there are no new ideas, I can use speedmeter with analog output. Michal.
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