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About pop29684

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  1. Turning CW and CCw after a delay

    I cannot think of any application where you would want to logically start/run a motor without any logical means to stop it. However, if you are so determined then press the PB once to start the motor. Then disconnect the PB from the PLC. The state of Y2 can also be directly manipulated while online in the software. If you choose to do this then there is no need for the first rung of the logic.
  2. easyE4 nanoPLC

    What is your application? If it is only a home use or learning exercise then I would consider using a Raspberry Pi loaded with CoDesys.
  3. I just recently began using ProjectLibre, which is an open source software. You can download it here: https://sourceforge.net/projects/projectlibre/. My decision to use this software: 1. It isn't Microsoft! 2. It is open source. 3. It will import Microsoft Project files (my primary reason - oh, you thought it was reason number 1? LOL.) After using this software now for a few weeks, I like it. If you have ever used Microsoft Project then you should be able to use this software.
  4. SIEMENS S7 200

    I think I understand what you are trying to accomplish: 1. Turn on a buzzer output for 3 seconds when a PB is pressed; buzzer must continue to sound for the full 3 second period even if the PB is released before the timeout period (3s). 2. Re-trigger the buzzer timer for another 3 seconds if the PB is released and pressed before the initial 3 second period has timed out. The solution is not readily seen because normally one would think that the trigger/re-trigger logic would apply only to the timer. This is not possible because an extended pulse timer cannot be re-triggered until it has timed out. A standard TON will not work because releasing the input PB before the timer has timed out will cause an immediate reset of the timer and the buzzer will turn off. However, a solution is possible: use a re-triggerable timer (TON) but latch the buzzer output directly from the PB press. Test the logic below. I think it will do what you wish. I don't have a 224 CPU to test. Let me know if this is what you are trying to do. EDIT 5 JULY 2019: I just tested this in the simulator. It works. Change the timer preset (PT) value to  300.
  5. Remote connection using eWon

    I've never used eWon but isn't that a Chinese product that connects to Chinese servers? Given the uncertainty of their security, I would suggest using Siemens Sinema.

    Analysis: the integer value stored in VB50 (decimal "1") is sent to the 7-segment display (QB5) when bits M0.3 AND M17.1 are both true (high, ON, 1). The 7-segment display must see segments b and c both equal 1; all other segments must equal 0. The S7-200 manual (p325) shows the relationship between the integer value to be displayed and the corresponding segments that must be ON for the correct value to be seen on the 7-segment display. The 7 segments are ordered from "a" to "-", with segment "a" being the LSB of the byte and "-" being the MSB of the byte. In the network example you provided, only integers 1, 2, 3, 4, and 0 are displayed on the 7-segment display. These integer values can be directly converted to a decimal value that will turn on the corresponding segments of the 7-segment display. The resulting code is shown below. It is a direct replacement of your network 76 without inventing a module to act as the "SEG" instruction. Nice, quick, simple, and easy. Just what the doctor ordered! :) Edit 18 June 2019: The absence of the "SEG" instruction for the 12## series CPUs is not due to the TIA Portal programming software. Rather it is because of the CPU (hardware) you are working with. The "SEG" instruction is available in TIA Portal when working with 15## and 3## series CPUs. I suspect the instruction is also available for the 4## series CPUs but I cannot confirm this because I don't have any current projects in TIA Portal that use this series of hardware.  The TIA Portal software only allows access to instructions compatible with the hardware you are programming.  
  7. Controlling Cylinder Stroke Length

    1. How is the cylinder actuated: pneumatic, hydraulic, electrically driven? 2. How is position being determined?
  8. How to replace a safety output card (1734-OB8S)?

    What makes you suspect the card is defective?
  9. problem with keyence

    If the program has been set to read protect you will not be able to upload the program from the CPU into the KV LadderBuilder software. I seem to remember, however, that you can still go onlline and monitor. It's been a long time since I've dabbled with the Keyence KV series and I don't have one handy with which to test my recollection. I've never used the Keyence Backup Tool software so I can't help you in any way with that. If you have hardcopy (printout) of the PLC program, search through it for the MEMSW instruction. This is the instruction that enables/disables read and write protection of the PLC program (and a number of other things, also). This instruction is detailed in volume three of the "User's Manual". The discussion begins on page 3-92. If you do not have a manual it is available from the dowload section of this site.
  10. Pop up login screen editing

    What PB press on the screen causes the pop-up? I would look at the programming of that PB. It could be directly programmed, use a script, macro, or something similar.
  11. How can I do a simple sequence step delay

    I've given a little more thought to your question and I think I have a single-network solution that will work for you. As you can see, this compiled without any errors. The difference is the use of the "isolation" condition, in this case "mLog1" (an "Always True", "ATI", or similar name). The N.O. contact shown could just as easily be replaced with an N.C. contact of "tStep_Dwell.Q". The effect of using the timer done bit would be to make the network execution function as a one-shot. Also note the absence of an output instruction on the "Q" output of the timer. This logic was designed in TIA v12.  
  12. How can I do a simple sequence step delay

    Hmmmmmm. I went to the Siemens forum and found an item that discusses this very issue. It is dated from 04 NOV 2011. Here is the link (https://support.industry.siemens.com/cs/document/54684852/in-step-7-(tia-portal)-why-is-it-not-possible-to-branch-to-a-move-instruction-for-the-s7-300-400-before-the-in-parameters-of-the-iec-timers-counters-?dti=0&lc=en-WW) but I don't know if you will be able to view it without signing in to an account or not. It is free to create an account and there is a lot of good information there. The article shows two different IEC timer functions, one with "EN/ENO" connections and one without. I don't want to copy and paste the information here because I don't want to infringe any copyrights. I would highly recommend creating an account just to view the discussion. In the mean time, the bottom line is that you were able to resolve the issue. Maybe not the way you would have liked or the way you are used to, but you've made it work. Good job!
  13. How can I do a simple sequence step delay

    I see in your initial post an error message relating to the use of an IEC timer. The TON is an IEC timer. What was the complete message? What did you do to resolve the error?
  14. How can I do a simple sequence step delay

    What is your frustration? Do neither forms work? I've used both successfully, although I prefer the second. Does TIA require the placeholder output instruction?
  15. Siemems Set Reset with singal input

    Another variation of Travis' logic can be found here: http://forums.mrplc.com/index.php?/files/file/1073-fc2-toggle-a-bit/. The logic uses two rungs but does not need the (S) and (R) instructions.