JesperMP

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Posts posted by JesperMP

  1. Posted

    Hi Greg. Not sure what you mean by "define symbols to a CP343-1". You can change the name of the modules used in the S7-300 station in the Hardware Configurator. But it does not have much effect or purpose. Symbols are used when programming the PLC code that runs in the CPU. Symbols are used in stead of absolute addresses. I.e. "Test_mode" is for M100.0 "Recipe".No1.component1 is for DB20.DBW40. You can setup symbols in the Symbols editor, and for DBs you define the symbols inside by creating declarations with the LAD/FBD/STL editor. It is generally recommended to switch from Absolute Address priority to Symbolic Address priority (Simatic Manager .. Right Click on "Blocks" and open the "Properties", the chose the "Adress Priority" tab).

  3. Posted

    by the way. If you happen to have the original STEP7 program, then there is a pretty good chance that the Protool or WinCC Flex projects are stored together with the program files. Look in the TDOP folder for a .pdb file (Protool source), and look in the HMIES folder for a .hmi file (WinCC Flex source).

  4. Posted

    Actually, I think there is a guarantee that you can NOT upload the full project from the TP170A panel. Not only must the original programmer download the program with the backtransfer option turned on, but there must be a flashcard in the panel for the storage. And I think that on a TP170A panel, there is no slot for an optional flash card. You are looking at getting the original Protool or WinCC Flex source program, or rewriting from scratch.

  6. Posted

    I cant help it. I have to comment that a laptop, and one that is shared between several users, is not where projects should be stored without backing them up. Windows and STEP7 and the licenses can be reinstalled or recovered. But the project files are gone when they are gone. This time it was a virus. Next time the laptop may be stolen, or run over by a truck, or the harddisk may be helplessly corrupted, or someone may goof up, or .... ..... etc. If you can get the project files out of the PC, consider yourself lucky.

  7. Posted · Edited by JesperMP

    No no no no.If a DP slave is lost, then the master will get a bus fault, but it will not stop the bus. The master will continue to update the other slaves. In some cases, a faulty slave can cause the entire bus to fault. One such case is if the slave is physically at the end of the Profibus cables daisy-chain. If the cable is removed from this slave, or the slave is powered down, then it may cause the termination to fail. This may again cause the a complete bus fault. This is the reason why there are active bus terminators. This so the critical termination isnt dependent on any of the bus stations. Another method is to use Profibus repeaters. Repeaters are not necessary for DP slaves that are within the limits of one segment. The CPU of the DP master may repsond in different ways to a bus fault, depending on the functionality and configuration. A Siemens PLC as a DP master, a Profibus fault may or may not stop the CPU. If this is not the desired result (in most cases it isnt), adding the appropriate error OBs to the program will prevent the PLC CPU from stopping. Typically the error OBs OB82, OB85, OB86, OB122 are added to the program. See the online help for what each of these error OBs do.

  8. Posted · Edited by JesperMP

    You certainly cannot simply exchange the CPU, move the MMC card to the new CPU, and swithc it to RUN mode.You will have to adapt both the hardware configuration, and possibly also the software. If some of the "technological functions" of the 313C (integral counter for example) have been used, it becomes even more complicated. Tell us more details about the application of the existing 313C, adn we can guide you better.

  9. Posted

    I dont think there were ever a "C compiler" for S5. I think there was the precursor to SCL, which is a Pascal like language for S7. Are you writing a history book about S5 ? Could be interesting. Surely you are not wasting any time on S5 with a view to actually make new programs to run on it ;)

  10. Posted

    If I understand correctly: You need 50 i/o nodes + 45 VFDs. That is not a small project, but one where the networking will be a critical backbone for the entire plant. Would never chose Modbus for such a project. With so many nodes, the likelyhood that a problem may occur is relatively high, and the consequences will be relatively expensive too. So dont be penny-pinching on this part of the project. I would chose an ethernet-based fieldbus (that does not include Modbus TCP), and I would arrange it in a ring with automatic switch-over. Think about that you most probably must be able to maintain the system including the networking without shutting down the plant. If this is possible with Modicon, I dont know, but the idea to use a mix of Modbus and CAN sounds as if the Modicon salesguy is trying to squeze in the lowest possible price because that is what he think is what you want. That you are even considering a Twido for such a job, somehow I think you are not the right person for this job.

  11. Posted

    I am fairly certain that the -32768..+32767 bracketing and NaN will be the result of bad math on an SLC500. I assumed that it would be the same on a PLC5.If it does not behave like that on a PLC5, then pinpointing a programming error on a PLC5 will be a bitch. The best I can think of is to stick several tests for math overflow in each program file that contains some math or counting.

  12. Posted

    Hi wildswing. You can trawl through all integer files and look for "-32768" or "32767" values, and all floating point files for "NaN" values. If you find any of these, you can use the x-ref to search for all occurences of the affected addreses. It is not a guaranteed method because the addresses can be overwritten after the overflow. But worth a try.

  13. Posted

    I forgot: In order to bring the cost down, while still using ethernet, think about using Beckhoff in stead of Siemens or Rockwell for the i/o modules. Beckhoff cost approximately half of Siemens modules, and approximately a third of Rockwell modules. And Beckhoff has just recently released a low-cost adapter module for Profinet. It does not have an integral switch, so you cannot daisy-chain from one adapter to the other, but maybe that should be avoided anyway.

  14. Posted

    With 100 nodes or more, I think that the serial fieldbuses will soon be stretched beyond their limits. That goes for Profibus DP, Devicenet, CAN, ASI. Of course, you can split the plant into several groups, so each group does not consist of so many nodes. If this is a very large plant, with long distances, and/or really many nodes, but with a relatively modest requirement for update speed, then maybe a more proces oriented fieldbus will be suited. That would be Foundation Fieldbus or Profibus PA. Apart from that, I think it is possibly a clear case for an Ethernet type fieldbus. Think Profinet or Ethernet/IP. You should absolutely arrange a "backbone" in the shape of a ring of swithces connected by fiber. Then connect from the switches to local nodes by means of shorter copper drop cables. That will mean you get a flexible and error-resistant system. I do not aggree with the notion that since there are many nodes, one should try to squeze the cost down. It is the other way around. With such a large plant with so many nodes, a small error can have much bigger consequences than on a single small machine. So it pays dividends to think in how to prevent one fault from bringing the whole system down, and how to pinpoint an error to fix it quickly.

  15. Posted

    "our remote I/O" ?, "the card" ? Exact information up front is cruicial to be able to provide any assistance. IF the remote i/o is an ET200S, then check that all modules including the terminator block at the very right end are all snapped properly into place. Exchange the IM module. Exchange the PM module(s).

  19. Posted

    I am using a laptop rated backpack. Not too big, not too small. Does not have the wheels for dragging along in the airport but sure beats carrying the case in the hand. The types with the wheels are sometimes problematic to get rid of in the overhead compartments. Believe me, you dont want to have to sit with the case in the front of you on long haul distances. As for tools, I have a real toolbox, and work clothes with pockets for carrying the most frequently used tools on me. For air travel, dont put any tools in you carry-on bag ! If didnt have to travel so frequently I would probably have a wheeled hard case.

  20. Posted

    Hi Sebu. You need WinCC Flexible ES Advanced to be able to create a PC RT. Siemens sample projects are almost always in panel versions as well as PC RT versions. So try to find the sample project with a panel in stead of a PC RT.

  25. Posted

    Both !There is literally manyears stored in my source code. However, after so much tweaking and modification, I have to admit that it does not look pretty any more. Btw. with STEP7 v5.5, an unbreakable know-how-protect is coming.