Siemens PLC, NC training materials

1. The use of CPU 315F and ET 200S should be how to avoid a "communication failure" message?

    The use of CPU S7 315F, ET 200S fail-safe as well as DI / DO module, then you will call the OB35 of the fail-safe procedure. Also, you have to accept all the default settings control the time and are willing to receive "communication failure" message. OB 35 default setting is 100 milliseconds. You have to FI / O modules, F monitoring time is set to 100 milliseconds, so at least once every 100 milliseconds to address I / O modules. However, due to only call once every 100 milliseconds OB 35, so communication failure occurs. OB35 to ensure that the scan interval and F monitoring time has been different, please ensure that the F monitoring time is greater than the scan interval OB35.

    S7 Distributed Safety System, until the V5.2 SP1 and 6ES7138-4FA00-0AB0, 6ES7138-4FB00-0AB0, 6ES7138-4CF00-0AB0 will have such problems. In the new module, F monitoring time is set to 150 milliseconds.

    2. When the DP is not available from the station, PROFIBUS on the S7-300 CPU to monitor how much time?

    Use CPU-PROFIBUS interface DP slave operation of PROFIBUS networks, want to start checking the desired configuration during the configuration and the actual match. CPU Properties dialog box in the Startup tab shows two different time periods.

3. How to determine the power or buffer error, such as: battery failure?

    If the power supply (only S7-400) or buffer in a false triggering an event, then the CPU operating system to access OB81. After error correction and re-visit the OB81. Battery fault conditions, if the battery detection BATT.INDIC switch is activated, then the S7-400 only access to OB81. If there is no configuration OB81, the CPU will not enter the operating state STOP. If OB81 is not available, then when the power goes wrong, CPU is still running.

    4. For the S7 CPU on the I / O module (centralized or distributed) the allocation of address should pay attention to what the problem?

    Please note that to create the data area (such as a double-word) can not be configured in the process image of the boundary, because in the data block, only the border area below the image can be read into the process, it is not possible to access from the process image data. Therefore, these rules do not support this configuration: for example, in a 256-byte input process image of the address No. 254 pairs of an input configuration word. If we need such a site, you must adjust the size of process image (in the Properties in the CPU).

    5. S7 CPU in how to carry out the basic global data communications? What is needed to pay attention in communications?

    Global data communication for the exchange of small-capacity data, global data (GD) can be:

    Input and output

    Mark

    Block data

    Timer and Counter Function

    Data exchange means connected into the one-way or two-way between the GD Central CPU to exchange data in the form of packets. GD by GD ring ring number to identify.

    One-way connection: a CPU to multiple CPU can send a GD packet.

    Two-way connection: the connection between the two CPU: Each CPU can send and receive a GD packet.

    Must ensure that the receiving end CPU is not recognized global data reception. If you want to block via the corresponding communications (SFB, FB, or FC) to exchange data, you must be a connection between the communication block. By defining a connection, you can greatly simplify the communication block design. The definition of the communication block all calls are valid and do not always redefined.

    6. Can be S7-400 memory card for CPU 318-2DP do?

    In normal operation, only use the ordering number is 6ES7951-1K ... (Flash EPROM) and 6ES7951-1A ... (RAM) of the "short" "memory card.

    7. Although the LED lights, why can not the default CPU 31xC address of 124 and 125 read the full input?

    For the following models of CPU, please check whether the access pin 24V voltage 1.LED from the input current control. Pin 1 on the 24V voltage needs to be done for further processing.

    313C (6ES7313-5BE0-0AB0), 313C-2DP (6ES7313-6CE0-0AB0), 313C-2PTP (6ES7313-6BE0-0AB0), 314C-2DP (6ES7314-6CF0-0AB0), 314C-2PTP (6ES7314-6BF0 - 0AB0)

    8. Configure CPU 31x-2 PN / DP interface of the PN, when the PROFINET interface, occasional communication error, the how to deal with?

    Make sure the Ethernet (PROFINET) all the components (conversion) support 100 Mbit / s full-duplex basic operation. Center divider to avoid the fragmented network, because these devices only work on the half-duplex mode.

    9. In the hardware configuration editor, the "clock" correction factor, what meaning?

    In the hardware configuration, through the CPU> Properties> Diagnostics / Clock, you can enter the "clock" "area specify a correction factor. This correction factor affects only the CPU's hardware clock. Time to break from the system clock and hardware clock settings and nothing.

    10. How to PROFIBUS DP with the functional blocks to achieve in the main, from the bi-directional data transmission between stations?

     Plc in the main station by calling SFC14 "DPRD_DAT" and SFC15 "DPWR_DAT" to complete the exchange of data to and from stations, and for speaking from the station can call FC1 "DP_SEND" and FC2 "DP_RECV" to complete the exchange of data.

    11. Can be read from the S7 CPU in which identification data?

    By SFC 51 "RDSYSST" read out the following identification data:

    Order number and the CPU can read out the version number. To do this, use the SFC 51 and SSL ID 0111 and use the following indexes:

    1 = Module ID

    6 = basic hardware identification

    7 = basic firmware ID

    12. CPU 317-2PN/DP containing the S7-300, on how the program can be loaded communication function blocks FB14 ( "GET"), and FB15 ( "PUT") for data exchange?

    In order to pass an S7 connection using the CPU 317-2PN/DP two S7-300 to exchange data between workstations, including the S7 connection is the use of NetPro configuration, "in the S7 communication, you must call the communication function blocks. Module FB14 ( "GET") used to extract data from a remote CPU, the module FB15 ( "PUT") is used to write data to a remote CPU. Functional blocks included in the STEP 7 V5.3 standard library.

    CPU 317-2PN/DP communication module FB14 ( "GET"), and FB15 ( "PUT") attributes:

FB14 and FB15 is asynchronous communication. The operation of these modules may span several OB1 cycle. Through the input parameter REQ activated FB14 or FB15. DONE, NDR, or ERROR that job ended. PUT and GET can simultaneously communicate through connections.

    Note: You can not be in the communication library SIMATIC_NET_CP block for CPU317-2PN/DP.

    13. For a compact CPU 313C-2 PtP and CPU 314-2 PtP operation synchronized to note what is?

    In the user program, can not at the same time programming SEND operations and FETCH operations.

    Namely: as long as the SEND operation (SFB 63) is not fully terminated (DONE or ERROR), can not call FETCH operation (SFB 64) (even in the REQ = 0 of course). As long as the FETCH operation (SFB 64) is not fully terminated (DONE or ERROR), can not call the SEND operation (SFB 63) (even in the REQ = 0 of course). In dealing with an active job (SEND operation, SFB 63, or FETCH operation, SFB 64) at the same time can deal with a passive job (SERVE operations, SFB 65).

    14. MICROMASTER 420 Dao 440 can be configured as an axis (position outside inspection) and the CPU 317T with the running?

    Yes, but in the power and precision on the configuration requirements of different axis very large. In demanding cases, the servo drives SIMODRIVE 611U, MASTERDRIVES MC or SINAMICS S must be run with the CPU 317T. In less demanding situations, MICROMASTER family also can meet the power and precision.

    15. How are configured to DP slave configuration between the two CPU modules direct data exchange (inter-node communication)?

    2 CPU configured as DP slave station, but also by the same DP master operation, the communication between them through the configuration mode for the exchange of DX can perform direct data exchange.

    16. How to use SFC65, SFC66, SFC67 and SFC68 to communicate?

    For the basic one-way communication, using the system function SFC67 (X_GET) reading data from a passive station, use the system function SFC68 (X_PUT) to write data to a passive station (server). These blocks only in the active station was called. For a basic two-way communication, the system function call station SFC65 (X_SEND), at the station wants to take the initiative to send data to another station. To active initiative in the same terminal, the data will be through the system function SFC66 (X_RCV) record.

    Two types of basic communication, each block can handle up to 76 bytes of call user data. For the S7-300 CPU, data transmission, data consistency is 8 bytes, for the S7-400 CPU is a full-length. If you connect to the S7-200, must take into account the S7-200 can only be used as a passive station.

    17. What is the free distribution of I / O address?

     Address of the free distribution means that you can for each module (SM / FM / CP) free distribution of an address. Address assignment, conducted in the STEP 7. First define the starting address, the module's other address it as a benchmark.

     Address the advantages of free distribution: Because there is no address gaps between modules, you can optimize use of available address space. When you create standard software, the allocation of addresses may not take into account the process involved in the S7-300 configuration.

    18. Diagnostic buffer to do?

    More quickly identify sources of error, and thus improve system availability. STOP before assessing the final event, and find the reasons causing STOP.

    Diagnostic buffer is a cycle with a single diagnostic buffer entries, these entries appear in the diagnostic sequence of events; the first entry shows the most recent events. If the buffer is full, the earliest events will be covered by the new entry. Depending on the CPU, the size of the diagnostic buffer, or fixed, or HW Config can be set through parameters.

    19. Diagnostic buffer entries include?

    1) failure event

    2) changing the mode of operation as well as other important operational events to users

    3) user-defined diagnostic event (with SFC52 WR_USMSG)

    In STOP mode of operation, the buffer in as little as possible in the diagnosis of storage events, so that users can easily be found in the buffer caused by STOP reasons. Therefore, only when the event requires the user to generate a response (such as the planning system memory reset, the battery needs to be charged), or must be registered important information (such as firmware updates, station failure) only when the entry is stored in the diagnostic buffer.

    20. How to determine the size of the MMC in order to store a complete STEP 7 project?

    In order to choose the right project MMC, need to understand the size of the entire project and the need to load the block size. Can follow the method described below to determine the size of the project:

    1) First filed STEP 7 project. And then in Windows Explorer, open the archived items, and determine its size (select the item and right-click). This will tell you the size of the archive file.

    2) to block Canadian loaded CPU. Still need to select "PLC> Module Information> Memory". Here, in the "Load memory RAM + EPROM", you can see the size of the memory allocated load.

    3) It must have been determined by the value and the size of the sum of archiving projects. This can be drawn on a MMC to save the entire project the total memory size required.

21.CPU full reset which settings will be retained after?

    Reset the CPU, the memory has not been completely removed. The main memory has been completely removed, but the data loaded in memory, and stored in Flash-EPROM memory card (MC) or micro memory card (MMC) on the data, it will all be preserved. In addition to loads of memory outside the timer (CPU 312 IFM, except) and the diagnostic buffer has also been retained. With the MPI interface or a combination of MPI / DP interface is reset before the CPU is only retained in all interfaces used by the current address and baud rate. On the other hand, another PROFIBUS address has also been completely deleted can no longer access.

    Important: to re-set the PG / PC Since then, communication between the CPU only through MPI or MPI / DP interface to establish.

    22. Why can not MPI-line access to CPU?

    If the CPU has been changed on the MPI parameters, please check the hardware configuration. You can combine these values with the "Set PG / PC interface" under the parameters of comparison, to see if there are inconsistencies.

    Or you can do: Open a new project, create a new hardware configuration. In the CPU of the MPI interface properties for the address and the transmission speed setting their values. The "empty" project written to the storage card. To the memory card inserted into the CPU and then re-open the CPU voltage, will be located on the memory card is set to send to the CPU. Has now been sent the MPI interface of the current settings, and the like, so long as there is no fault interface connection can be established. This method applies to all have a memory card interface S7-CPU.

    23. Error OB what is the use?

    As described in the event of an error (see document 1), will be called and processed the corresponding OB. If there is no load to the OB, then the CPU into STOP (exception: OB70, 72,73 and 81)

    S7-CPU can identify two types of errors:

    1) synchronization error: These errors in dealing with the process of specific actions are triggered, and can be attributed to a specific part of the user program.

    2) Asynchronous Error: These errors can not be directly attributed to running programs. These errors include the priority class of the error, automated system error (fault module) or redundant errors.

    24. In the DP from the station or CPU315-2DP-type main station's programming should be what "fault OBs"?

    As a slave in the configuration of the CPU315-2DP station must be programmed in the STEP7 program in order to assess the following OB Distributed I / O type of error message:

    OB82 Diagnostic Interrupt OB, OB 86 sub-rack failure OB, OB122 I / O access error

    1) Diagnosis OB82: If a support for the diagnosis, and has released its diagnostic interrupt module to identify an error, both right out into the incident to the incident to the CPU to send a diagnostic interrupt request. The operating system then calls OB82. In OB82's own local variable inside the module containing the defective logical base address and 4 bytes of diagnostic data. If you do not program OB82, the CPU into the "stop" mode. You can block or delay the diagnostic interrupt OB, and through SFC 39 - 42 re-release it.

    2) The sub-rack failure OB86: If you identify a DP master station system or a distributed I / O stations are there fault (both right into the incident right out of the event), the CPU's operating system calls the OB 86. If there is no programming OB 86, but such an error occurs, CPU enters the "stop" mode. You can block or delay the OB86, and through SFC39-42 re-release it.

    3) I / O access error OB122: when accessing data in a module error, the CPU's operating system to call OB 122. For example, CPU while accessing data in a single module to identify a read error, then the operating system called OB 122. The OB 122 in order to break blocks with the same priority class to run. If there is no programming OB 122, then the CPU from the "Run" mode to "stop" mode.

    25. Why, in some cases, the reserve will be rewritten?

    In the STEP 7 hardware configuration, you can put a few operands area is defined as "reserves." This allows power-down later, even without the backup battery if it maintains the content of these regions. If you define a block as the "reserved blocks", and it does not exist in the CPU or only a temporary installation, then the parts of these regions will be rewritten. In the power on / off, the other content will be found in the relevant areas.

    26. Why can not the contents of flash memory cards plus load S7-300CPU?

    Your project in the flash memory card. Now to use it loads S7300. But the load was found after the end of the RAM in the CPU is still empty. This problem occurs because your application there can not handle it, "wrong" organization block (for example, OB86 not DP interface). Re-set and re-start the CPU after, RAM is still empty. Diagnostic buffer of this "Unable to load" block will be prompted to some information.

    27. When the CPU315-2DP as slave, the CPU315-2DP as the main station, the diagnosis of address

   In the configuration of a CPU315-2DP station, you use the S7 tool "H / W CONFIG" to assign diagnostic address. In the event of a failure, these diagnostic OB addresses be added to the variable diagnosed "OB82_MDL_ADDR" Lane. You can OB82 where an analysis of this variable to determine the faulty station and respond accordingly.

    The following are examples of how to allocate diagnostic address:

    Step 1: Adoption of the CPU315-2DP configuration from the station and given a diagnosis of address, such as 422.

    Step 2: Adoption of the CPU315-2DP Configuration Master

    Step 3: the configuration of a good link to the main station from the station and given a diagnosis of address, such as

1022.

    28. The need for S7-300 CPU of the DP slave interface to what is set before you can use it to carry out route selection?

    If you use the CPU as an I-Slave, and that the CPU also played the role of S7 router, then please note the following:

    For the routing of the DP slave interface must be set to active. This can be completed in the HW Config: In the D interface Properties dialog box, the option "" Commissioning / Test operation "or" Programming, status / modify ... "must be activated. Note on these settings can be obtained in the following table.

    For the S7 routing connections, there are four kinds of available connection resources, has nothing to do with any other connection resources. Do not use PG / OP connection resources or S7 basic communication.

    If you have to through the DP interface to build a rack located in their communication partners in connection (as in the CP343-1 middle), also using a routing connection. For through the MPI interface with a rack located in their communication partners, the connection is not using the routing connection resources, since in this case, can directly reach the partner. Note: This does not apply to CPU 318.

    29. Why, when using the S7-300 CPU's internal operating timetable, there is no return value?

    When the CPU 312IFM to the 316-2DP parameterized system function blocks SFC2, SFC3 and SFC4 time, in a running schedule provides for a greater than "B # 16 # 0" identifier, then an error and the required functionality can not be used. This case, would block "RETVAL" output at the output identifier "8080h".

    Note: For the CPU, there is only one timer is available. So you should only use the identifier "B # 16 # 0". In a cycle block (OB1, OB35) where we must not call the system function SFC2 "SET_RTM", but should restart OB (OB100) call it. You can also use an external trigger to start the block. Otherwise, the block will always reset the run time sheets, never count will not be completed.

    30. Variable is how the local data stored in the temporary in?

    L stack is always in order to address "0" start. In the L stack for each data block to keep the same number of bytes, each block as the store owned by a static or local data. When a block is terminated, then it is also the space subsequently re-released. Pointer always points to the current block to open the first one byte.