Compound Dosing with SIWAREX FTA in the PCS 7 environment

Transcription

1 Application description 08/2014 Compound Dosing with SIWAREX FTA in the PCS 7 environment SIMATIC PCS 7 and SIWAREX Advanced Process Library

2 Warranty and liability Warranty and liability Note The Application Examples are not binding and do not claim to be complete regarding the circuits shown, equipping and any eventuality. The Application Examples do not represent customer-specific solutions. They are only intended to provide support for typical applications. You are responsible for ensuring that the described products are used correctly. These application examples do not relieve you of the responsibility to use safe practices in application, installation, operation and maintenance. When using these Application Examples, you recognize that we cannot be made liable for any damage/claims beyond the liability clause described. We reserve the right to make changes to these Application Examples at any time without prior notice. If there are any deviations between the recommendations provided in these application examples and other Siemens publications e.g. Catalogs the contents of the other documents have priority. We do not accept any liability for the information contained in this document. Any claims against us based on whatever legal reason resulting from the use of the examples, information, programs, engineering and performance data etc., described in this Application Example shall be excluded. Such an exclusion shall not apply in the case of mandatory liability, e.g. under the German Product Liability Act ( Produkthaftungsgesetz ), in case of intent, gross negligence, or injury of life, body or health, guarantee for the quality of a product, fraudulent concealment of a deficiency or breach of a condition which goes to the root of the contract ( wesentliche Vertragspflichten ). The damages for a breach of a substantial contractual obligation are, however, limited to the foreseeable damage, typical for the type of contract, except in the event of intent or gross negligence or injury to life, body or health. The above provisions do not imply a change of the burden of proof to your detriment. Any form of duplication or distribution of these Application Examples or excerpts hereof is prohibited without the expressed consent of Siemens Industry Sector. Security information Siemens provides products and solutions with industrial security functions that support the secure operation of plants, solutions, machines, equipment and/or networks. They are important components in a holistic industrial security concept. With this in mind, Siemens products and solutions undergo continuous development. Siemens recommends strongly that you regularly check for product updates. For the secure operation of Siemens products and solutions, it is necessary to take suitable preventive action (e.g. cell protection concept) and integrate each component into a holistic, state-of-the-art industrial security concept. Third-party products that may be in use should also be considered. For more information about industrial security, visit To stay informed about product updates as they occur, sign up for a productspecific newsletter. For more information, visit Entry ID: , V1.0, 08/2014 2

3 Table of contents Table of contents Warranty and liability Taskdescription and solution Task Solution General library information Dosing versions Requirements Hardware requirements Software requirement Ordering and scope of delivery Installation Configuration and start-up Configuring the hardware Configuring the function blocks Commissioning / Adjustment Adjustment parameters (DR 3) Adjustment via faceplate Basic parameter (DR 4) Interface parameters (DR 7) Scale parameter 2 (DR 23) Configuring requirements Requirement Process values 1, 2 and status Access to status bits from AWI and NAWI Logging of dosing operations Monitoring limit value Monitoring the dosing steps Checking the dosing for tolerance Optimizing the cut-off time points On site analog value display Configuring the control recipe phase Installation of the SFC types Characteristics of the SFC type "START" chain "Dosing_Comp1" chain "Dosing_Comp2" chain "Dosing_Comp3" chain "Emptying" chain "Complete" chain "HOLDING" chain "HOLD" chain "RESUME" chain "ABORT" chain Additional configurations required History Entry ID: , V1.0, 08/2014 3

4 1 Taskdescription and solution 1 Taskdescription and solution 1.1 Task Dosing and weighing operations are often required in process automation. Different types of electronic weighing systems are used depending on the requirements of the process. The SIWAREX FTA and SIWAREX U have been approved for use in the PCS 7 environment as an electronic weighing system. The following table shows both modules with respect to different areas of application. Table 1-1 Order number SIWAREX U 7MH4950-1AA01 (single channel version) SIWAREX FTA 7MH4900-2AA01 Typical areas of application Integration into automation systems 7MH4950-2AA01 (two-channel version) Simple weighing and force measuring tasks such as platform weighing machines or level measurements in silos or bunkers S7-300 (directly or via ET 200M) S7-400 (H), PCS 7 (H) (via ET 200M) Automatic and nonautomatic weighing operation for the production of mixtures, filling, loading, monitoring, weighing checks and bagging S7-300 (directly or via ET 200M) S7-400 (H), PCS 7 (H) (via ET 200M) Resolution 65,000 parts 16 million parts Permitted ATEX 95, FM, CULUS ATEX 95, FM, UCLUS, EU type examination according to MID (CE, OIML R76), EU type examination according to MID (OIML R51, R61, R107) for custody transfer applications. Note The following descriptions only relate to the SIWAREX FTA. You can find an Application Example for the SIWAREX U in the Siemens Industry Online Support portal under the Entry ID In the process industry, a common use of the electronic weighing system is the dosing of one or more substances in a reactor. The dosing operation should be, as much as possible: Accurate Fast Adaptable to various substance properties, in the limited context Entry ID: , V1.0, 08/2014 4

5 1 Taskdescription and solution 1.2 Solution The following Application Example describes the application of a dosage in the PCS 7 environment. Three different components in an individual process are to be dosed into a reactor according to the recipe. The following requirements are imposed on the solution: The empty reactor has a weight of 750 kg (= dead load), it should achieve an accuracy of ± 300 g. After each dosage and based on tolerance signals, it should be decided whether the dosage was "good" or not. The individual steps of the doses (tare, coarse/fine signal, tolerance checking, dosing completed...) should be always monitored. The scale should automatically optimize the coarse and fine signal cut-off points for the individual components. To increase process safety, a monitoring limit value signal should be defined. On the one hand, this should be evaluated in the AS, as well as control a horn directly on site. To ensure quality, each dose should be logged with time stamp, product name, time and weight. In addition, a locally preexisting analog value indicator should display the current total capacity of the scale using a 4-20 ma signal. The Application Example provides a template that comprises all typical components, their control system, the necessary logic as well as the visualization. The figure below describes the schematic structure of the solution: Entry ID: , V1.0, 08/2014 5

6 1 Taskdescription and solution Customer benefits The following configuration example enables you to significantly reduce your engineering effort when using PCS 7 standard agents while improving performance. You can use the solution for both new configurations as well as for integration into existing projects. The required hardware and software products are all made by Siemens and guarantee the compatibility, actuality and upgrade options you are accustomed to. When using the SIWAREX FTA - Advanced Process Library you also get the following benefits A reduction of the knowledge necessary to develop applications A decrease in the configuration effort Flexible installation and customization through reusability of the program structures used Guaranteed Siemens support Standardized and tested solutions Engineering in a familiar PCS 7 environment Library module with online help (F1) in German and English Setup in German and English Core contents of the application description Advantages Required hardware and software Installation and assembly Adjustment Configuring of functions Validity The SIWAREX FTA Advanced Process Library modules used in this application description have been approved for use with all PCS 7 versions starting from PCS 7 V8.0 Update 1. The description and screenshots of the described configuration example have been made with PCS 7 V8.0 SP1. Entry ID: , V1.0, 08/2014 6

7 2 General library information 2 General library information Mode of operation The library is used to connect the SIWAREX FTA to PCS 7 via APL-compliant devices. The library consists of these three modules: Channel and function block "SftAwi" for scale functionality, "CMD_AWI" for command control "MOD_SIWA" for maintenance The "SftAwi" module serves as a channel and Function Block. This allows data to be transfered cyclically via the peripheral interface and the various data records to be read from or written to the module acyclically. The block icon and the corresponding faceplate allow the scale to be adjusted and, for example, to manually start a dosing operation. Command block Maintenance block Text library The "CMD_AWI" block serves as an upstream block for the automatic commands of the "SftAwi". Not used in this Application Example. In addition to the blocks, the library also contains a text library with the message texts and block icons for operation via the Operator Station (hereinafter abbreviated to OS). Entry ID: , V1.0, 08/2014 7

8 2 General library information 2.1 Dosing versions Various dosing versions can be accomplished with the SIWAREX FTA. Both additive and subtractive dosing operations can be accomplished with or without subsequent emptying. In this Application Example, an additive dosage is described without subsequent emptying. Emptying is carried out separately after dosing. Note A complete description of the various dosing versions is available in the "SIWAREX FTA - Device Manual", from Chapter "DR 4 Scale operating mode" Entry ID: , V1.0, 08/2014 8

9 2 General library information 2.2 Requirements Hardware requirements The conditions of STEP 7 and WinCC apply for installation. In addition, the relevant requirements, e.g. the ones for the PCS 7 Basic Library V8.0, also apply. The library supports the functions of the SIWAREX FTA (7MH4900-2AA01) module. The following table lists the hardware components used in the Application Example: Table 2-1 Type Order number Firmware version CPU 417-4H 6ES HT14-0AB0 V4.5 CP Ext 6GK DX04-0XE0 V6.6 IM 153-2, redundant SIWAREX FTA SIWATOOL connecting cable, 2 m "SIWAREX FTA APL" configuration package Software requirement 6ES BA02-0XB0 7MH4900-2AA01 7MH4702-8CA 7MH4900-2AK65 The following software components are required for the dosing operation presented in this Application Example: SIWAREX FTA - Advanced Process Library SIMATIC PCS 7 from Version 8.0 Update Ordering and scope of delivery The SIWAREX FTA APL for SIMATIC PCS 7 V8.0 Update 1 configuration package can be purchased from the Siemens Industry Mall. Scope of delivery: Hardware Support Package (HSP) for S7 integration Function and channel blocks for CFC Block icon and faceplate for WinCC Online help (F1) SIWATOOL FTA PC software Manual (PDF format) in German and English Entry ID: , V1.0, 08/2014 9

10 2 General library information 2.4 Installation Scope of delivery The SIWAREX FTA is not found by default in the hardware catalog of the SIMATIC Manager. For this purpose, one needs to install an HSP which is available for download from Note Before installing the HSP, please go to installed software list the Windows Control Panel and check if there is an entry for "SIMATIC SIWAREX FTA Vx.x" or "SIMATIC SIWAREX FTC Vx.x". Should this be the case, the software must be uninstalled before proceeding with the installation! Installing the SIWAREX software The installation CD includes the "SIWAREX FTA - Advanced Process Library", sample project, HSP and the manuals in German and English. During installation, observe the instructions in the readme file under Chapter 4 "Installation and uninstallation" of the software. After running the setup program, you will find these components in the following paths: Library \Program Files (x86)\siemens\step7\s7libs PCS 7 faceplates \Program Files (x86)\siemens\wincc\options\pdl\apl Sample project \Program Files (x86)\siemens\step7\examples When you open the "SIWAREX FTA - Advanced Process Library" for the first time, use the "Browse" function from the "Open" dialog to access the "SFT_AWI_APL" library in the "S7Libs" Siemens folder. Entry ID: , V1.0, 08/

11 3 Configuration and start-up 3 Configuration and start-up User text library In addition to the error number, various messages in WinCC also contain error text from the user text library. The user text library must be copied by the user from the "Siwarex FTA APL" block library to the relevant project. 1. To do this, open the "Siwarex FTA APL" block library in SIMATIC Manager. 2. Select the "Text Libraries" folder and copy it into your project. If your project already contains a folder for user text libraries, copy the files "SFT_AWI_DAT_OP", "SFT_AWI_OP_MSG" and "SFT_AWI_TECH" from that folder to this folder. 3.1 Configuring the hardware After installing the HSP, you will find the SIWAREX FTA in the "Standard" catalog profile and it is pulled to the ET 200M via drag and drop. Figure 3-1 Entry ID: , V1.0, 08/

12 3 Configuration and start-up The input and output addresses must lie within the process image of the CPU. Figure 3-2 Once you have inserted the SIWAREX FTA and predefined the address range, save and compile the configuration, and close the hardware configuration. Entry ID: , V1.0, 08/

13 3 Configuration and start-up 3.2 Configuring the function blocks The following figure shows the first configuration steps in the Continuous Function Chart. Figure 3-3 The "Laddr" input of the "SftAwi" block must be connected with the assigned address in the hardware configuration. The PCS 7 driver wizard then installs all the required driver blocks automatically (the "Create module driver" option must be activated when compiling). The "Modf", "PeraF", "RackF", "MS", "DataXchg", "En_Co", "CpuDiag", "QParf", "ODiag" and "EnCo" are interconnected by the driver wizard and the "Subn1Id", "Subn2Id ", "RackNo", "SlotNo", "BasAdr", "Daddr "and "CoNo" inputs are parameterized according to the data from the hardware configuration. Note A sample CFC is available in the sample project for the SIWAREX FTA, which is included in the "SIWAREX FTA APL" configuration package. For more information, see the "SIWAREX FTA PCS 7 Advanced Process Library" Manual (Chapter 6, "Configuration Example"). Entry ID: , V1.0, 08/

14 3 Configuration and start-up The following table describes the connections between the two function blocks "SftAwi" and "CMD_AWI". Table 3-1 Module Output Block Input CMD_AWI AUT_CMD à SftAwi AutCmd CMD_AWI AUTCMDEN à SftAwi AutCmdEn SftAwi AutAct à CMD_AWI Man_Out SftAwi CmdFOK à CMD_AWI CMD_FOK SftAwi CmdErr à CMD_AWI CMD_ERR Activate the "Create block icon" option in the object properties of the" SftAwi" function block. This is necessary in order to enable adjustment and commissioning via the faceplate. Figure 3-4 Entry ID: , V1.0, 08/

15 3 Configuration and start-up 3.3 Commissioning / Adjustment Commissioning and adjustment are done with the help of the block icon or the faceplate and the "SftAwi" function block. In order to perform the commissioning and adjustment from the faceplate, the following requirements must be met: Hardware is correctly installed and wired User program is compiled and loaded OS is compiled and has connection to AS In the following chapters, descriptions only include those data records and their parameters that are required for commissioning and adjustment. All other data records and their parameters that are needed for the requirements described for the implementation of the chapter in 1.2 "solution" are described separately in the chapters belonging to the requirements Adjustment parameters (DR 3) Note The adjustment parameters of the SIWAREX FTA, which are required for the adjustment of the SIWAREX FTA are summarized in data record 3 (from now on, Data Record shall be abbreviated as DR). The scale is put into operation with these parameters and the adjustment. The adjustment parameters are to be checked for each scale and adjusted if needed. General procedure: Switch on service mode Check all parameters and adjust if needed Send DR 3 to the SIWAREX FTA Perform adjustment Read DR 3 from the SIWAREX FTA (in the SIMATIC controller, so that in the case of spare parts, the data can be loaded quickly into the module) Detailed information about the parameters of the DR 3 is available in the "SIWAREX FTA Device Manual", from Chapter 5.2 "DR 3 Adjustment parameter (NAWI, AWI)" Adjustment via faceplate The scale can be adjusted in the following ways: SIWATOOL FTA (by means of a PC and an RS232 connection) CFC (via SftAwi block and DR 3 parameters) In WinCC via faceplate (writes and reads parameters of DR 3) Entry ID: , V1.0, 08/

16 3 Configuration and start-up The following table describes the procedure for the adjustment in WinCC via the faceplate: Table 3-2 Step Action 1. Open the faceplate of the SIWAREX FTA by clicking the mouse on the block icon. The faceplate opens in the "Standard" view. Entry ID: , V1.0, 08/

17 3 Configuration and start-up Step Action 2. Check if the "Manual" operating mode is activated. If not, activate the "Manual" operating mode. 3. Switch to the "Operation" view and activate the "Service Mode". Entry ID: , V1.0, 08/

18 3 Configuration and start-up Step Action 4. Switch to "Calibration parameters 1" view and set the corresponding values for minimum and maximum weight 1 as well as the increment 1 (in Application Example 0 kg, 2100 kg and 0.020). Send the new parameters to the SIWAREX FTA. 5. Switch to "Calibration parameter 2" view and enter the weight of the adjustment weights in the "Adjustment weight 1" field. Entry ID: , V1.0, 08/

19 3 Configuration and start-up Step Action 6. Send the new parameters to the SIWAREX FTA and switch back to the "Operation" view. 7. Switch back to the "Operation" view. 8. Make sure that the load cell(s) is/are not loaded, or only the empty scale vessel is loaded on the load cell(s). 9. Run the adjustment command "Adjustment point 0 valid". The displayed net weight is set to zero. 10. Load the scale with the calibration weight entered in point Run the adjustment command "Adjustment point 1 valid". The displayed net weight is set to the value of the set adjustment weight for the supply (see point 5). 12. The scale is now adjusted. Finally, the determined adjustment parameter must be still read using "Receive Data" in the control system. This concludes the adjustment. 13. Deactivate the Service Mode Basic parameter (DR 4) The basic parameters define other features of the SIWAREX FTA that affect the overall behavior. Some can be defined directly via the faceplate. Others are to be defined at the "SftAwi" FB or alternatively by means of the SIWATOOL FTA. The following starts with a description of the parameters that are defined via the faceplate. Then, the parameters defined in the FB will be summarized and a description will be given of how they are defined. Note In principle, a definition of all parameters of the DR 4 is possible via the FB! Entry ID: , V1.0, 08/

20 3 Configuration and start-up Define the monitoring limit To increase process safety, a monitoring limit can be set. This should be selected to detect a possible overfill at an early stage. The SIWAREX FTA provides the ability to define and monitor three different limit values. The "Limit value 3" is particularly suitable for overfill monitoring. This is always based on the gross weight of the scale, so that a tare has no effect on the monitoring. The following table describes the definition of "Limit value 3" via the faceplate. Note The parameters for limit values 1 and 2 must be assigned directly at the "SftAwi" Block or by means of the SIWATOOL FTA. The limit values 1 and 2 can refer to the gross or net weight according to the setting. Table 3-3 No. Action 1. Open the faceplate of the SIWAREX FTA via the block icon 2. Make sure that the module is in the "Manual" operating mode and the "Service mode" is active. 3. Switch to the "Basic parameter" view. 4. Enter the values for the switch-on and cut-off limit value. Then, send them to the SIWAREX FTA. Note The value entry for the switch-on and cut-off limit values can define whether overfilling (switch-on limit value is greater than cut-off limit value) or a no-load operation (cut-off limit value is greater than switch-on limit value) is to be monitored. For more information, refer to the "SIWAREX FTA - Device Manual" Chapter "DR 4 - Switch-on weight limit value 1". Entry ID: , V1.0, 08/

21 3 Configuration and start-up Define empty range The definition of the empty range determines the limit value, which must be exceeded in order for the SIWAREX FTA to detect an "empty" state and to report it as status. The following table describes the definition of the empty range via the faceplate. Step Action 1. Open the faceplate of the SIWAREX FTA via the block icon. 2. Make sure that the module is in the "Manual" operating mode and the "Service mode" is active. 3. Switch to the "Basic parameter" view. 4. Enter the value for the empty range. Then, send it to the SIWAREX FTA. Whether the empty range refers to the current gross or net weight, this is defined via the "EmptyGn_M" input (see the point "Define further basic parameters in DR 4). Define further basic parameters in DR 4 The following table gives a summary of the parameters that are used in this Application Example and that must be defined in the CFC's "SftAwi" function block. Table 3-4 Parameter/Data Type Meaning Value SCType_M (Byte) Controller operating mode 16#3, dosing (additive) without final emptying ProtPara_M (Bool) EmptyGn_M (Bool) Device for the protocol output Basic weight for the monitoring of the empty range 1, protocol output on CompactFlash card 1, the gross weight is the basis for the empty range Entry ID: , V1.0, 08/

22 3 Configuration and start-up To transfer the parameters to the SIWAREX FTA, we recommend the procedure described in the following table: Table 3-5 Step Action 1. Open the CFC chart containing the "SftAwi" FB. 2. Switch the FB to "Manual" and activate the test mode. 3. Select the "SftAwi" FB and activate the "Monitoring ON" function. 4. Open the object properties of the FB. 5. Switch to the "Connectors" tab 6. Switch the following connections to visible: "ManCmd" "SCTyoe_M" "SCType_O" "ProtPara_M" "ProtPara_O" "EmptyGn_M" "EmptyGn_O" "Lim1On_M" "Lim1On_O" "Lim1Off_M" "Lim1Off_O" "Lim2On_M" "Lim2On_O" "Lim2Off_M" "Lim2Off_O" 7. Enter the value "204" at the input "ManCmd" (read data record 4). After a successful read, "ManCmd" is automatically set to Verify that the correct values are available at outputs "SCType_O", "ProtPara_O", "Lim1On_O", "Lim1Off_On", "Lim2On_O" and "Lim2Off_O". 9. If all values are correct, the parameters can be switched again to hidden. 10. If you need to change values, enter them at the inputs "SCType_M", "ProtPara_M", "Lim1On_M", "Lim1Off_M", "Lim2On_M" and "Lim2Off_M". 11. To send the new parameters to the scale, the value "404" (write data record 4) must be entered in the "ManCMD" parameter. After a successful write, "ManCmd" is automatically set to 0, 12. Then enter the value "204" at "ManCmd" and check whether the values have been written correctly to the module at outputs "SCType_O", "ProtPara_O", "Lim1On_O", "Lim1Off_On", "Lim2On_O" and "Lim2Off_O". 13. If the values have not been written correctly to the module, repeat steps 10 to 12. If all values are correct, the parameters can be switched again to hidden. Note For a detailed description of the above parameters, please refer to Chapter 5.4 "DR 4 Basic parameter" in the "SIWAREX FTA Device Manual". Entry ID: , V1.0, 08/

23 3 Configuration and start-up Interface parameters (DR 7) The behavior of the SIWAREX FTA is defined at the interfaces via the interface parameters. The interface parameters cannot be defined via the faceplate included in the library. Parameter assignment is carried out in the CFC at the "SftAwi" function block. Note The default values are to be kept for unused interfaces. The following table describes the parameters that must be assigned for the implementation of the requirements described in the Application Example. Table 3-6 Parameter/Data Type Meaning Value "DecPnt_M" (BYTE) "ProcV1_M" (BYTE) "ProcV2_M" (BYTE) "AoZero_M" (REAL) "AoEnd_M" (REAL) "AoScr_M" (BYTE) "Ao420_M" (BOOL) Decade for the rounding of the decimal places of process values Process value 1 for fast output to the SIMATIC CPU Process value 2 for fast output to the SIMATIC CPU Weight for zero point (0 or 4mA) for analog output Weight for the full-scale value (20mA) for analog output 16#0 3, 3 decimal places 16#02, net weight (process value) 16#30, AWI-Status 0,0, start of measuring range 2100, end of the measuring range Source for the analog output 16#02, current gross weight Current range for the analog output 1, 4-20mA "MmcPrOwr_M" (BOOL) Protocol overflow 0, overwritten "MmcTrsS_M" (BYTE) "MmcPrS_M" (BYTE) Memory section for trace function Memory share for protocol function 16#00, 0% memory share 16#64, 100% memory share Note The values for "ProcV1_M" and "ProcV2_M" may not be changed in the PCS 7 environment because the OS objects of SIWAREX FTA rely on its contained information. The checking and changing of the above mentioned parameter values is done as described in the chapter "Basic parameters (DR 4). The values for writing and reading of DR 7 are "207" (Read data record 7) and "407" (Write data record 7). Entry ID: , V1.0, 08/

24 3 Configuration and start-up Scale parameter 2 (DR 23) The DR 23 enables the combination of scale parameters which are normally typical to the scale and do not depend heavily on changing material properties. In the Application Example, only the "TxtNoA_M" parameter must be checked. All other parameters retain their factory setting. Table 3-7 Parameter/Data Type Meaning Value "TxtNoA_M" (BYTE) Text selection for automatic logging 16#01 The checking and changing of the above mentioned parameter values is done as described in the chapter "Basic parameters (DR 4). The values for writing and reading of DR 23 are "223" (Read data record 23) and "423" (Write data record 23). Entry ID: , V1.0, 08/

25 4 Configuring requirements 4 Configuring requirements The following chapters describe the configurations that are necessary to meet the requirements described in the chapter 1.2 "Solution". 4.1 Requirement To meet the requirements, you must fulfill the following conditions: SIWAREX FTA is adjusted and put in operation Current data and states of the SIWAREX FTA are known Process values 1, 2 and status Current data and states of the SIWAREX FTA can be monitored with the aid of process values 1, 2 and the status. The Application Example uses the Current net weight, AWI status and NAWI status parameters. The rule, which applies to all three parameters, is that instead of the outputs of the individual values, one must use the outputs defined in the chapter 0 "Interface parameters (DR 7)". This has the advantage that the current peripheral values are always accessible. It is not necessary to run the "230" command (read data record 30) at input "BackCMD". The status information is combined to form a double word. The following tables describe the information (bits) that can be used from the NAWI and AWI status for further processing. Table 4-1 NAWI-Status bits (= "ScStatus") Bit no. Name Range of values / meaning 0. WB1 Weight within weighing range 1 1. WB2 Weight within weighing range 2 2. WB3 Weight within weighing range 3 3. Limit 1 Limit value 1 activated 4. Limit 2 Limit value 2 activated 5. Limit 3 Limit value 3 activated 6. Tared (NET) Set if the scale is tarred 7. Preset Tare Set if the scale was tarred with tare input 8. Max+9e Set if maximum load is exceeded by 9 e 9. ¼ d-zero Set if the weight does not exceed ¼ d 10. Waiting for standstill Set if the scale waits for a standstill after the weighing start 11. Standstill 1 Standstill 1 exists 12. Scale adjusted Set if the scale is adjusted (calibrated) Entry ID: , V1.0, 08/

26 4 Configuring requirements Bit no. Name Range of values / meaning 13. Error on DI Set if a command could not be executed on a digital input 14. Simulation active Set if the weight simulation has been activated. 15. Service mode active Set if service operation has been activated. 16. Printing log The log is being printed. 17. RS232-Print not possible The log cannot be printed. 18. CompactFlash card inserted The CompactFlash card is in position. 19. CompactFlash card ready The CompactFlash card is formatted and ready for recording. 20. CompactFlash card-trace ready The CompactFlash card is ready for the trace function. 21. CompactFlash card-log ready The CompactFlash card is ready for logging. 22. Trace active The trace function is activated. 23. Min. through-put 1 overshot Throughput monitor 1 activated. 24. Min. through-put 2 overshot Throughput monitor 2 activated. 25. Empty message Scale in empty range 26. Calibration data protection The switch for protecting the calibration data is switched on. 27. Starting up Set during the warm-up phase (duration 1 min, no commands are assumed, the firmware version will be displayed in ascii-weight DR 34). 28. CompactFlash card data ready S7 Preparing the CompactFlash card data with the default in DR 46 for the S7 interface DR 47 has completed. 29. Digital LC active 0 = Digital load cell recording not active 1 = Digital load cell recording is active 30. Stand-alone operation 0 = SIMATIC operation activated 1 = Stand-alone operation activated 31. Operating error At least one operating error exists Table 4-2 AWI-Status bits (= "ProcVal2") Bit no. Name Range of values / meaning 0. Weighing step Current weighing control step 0 to Post dosing Post dosing is active. 9. Course signal The coarse signal is switched on. 10. Fine signal The fine signal is switched on. Entry ID: , V1.0, 08/

27 4 Configuring requirements Bit no. Name Range of values / meaning 11. Timer pre-dosing The timer for pre-dosing is active. 12. Empty signal The empty signal is switched on. 13. Weighing stopped The weighing cycle has been stopped. 14. Weighing stopped because of check stop The weighing cycle has been stopped because of the check stop command. 15. Check stop follows The weighing cycle will be stopped by a check stop (is set with the check stop command and reset if the check stop is achieved). 16. Last weighing procedure aborted Last weighing procedure aborted with Residual weighing or Reset weighing control. 17. Weighing blocked Set if the step-on to the next step in the weighing cycle is blocked because of a missing step release. 18. TO2 Net weight above the TO2 limit 19. TO1 Net weight above the TO1 limit 20. Good Net weight in tolerance TU1 to TO1 21. TU1 Net weight under TU1 but over TU2 limit 22. TU2 Net weight under TU2 limit 23. TOL bad Net weight under TU2 limit or over TO2 limit 24. Standstill 2 Standstill 2 exists. 25. Standstill 3 Standstill 3 exists. 26. Check to follow A weighing check is run at the end of the cycle. 27. Inhibit time active Weighing runs without weight evaluation! Operating error 17 is suppressed. 28. Continuous start active Continuous start for the cycle sequence is activated. 29. Reserve Cycle end Weighing cycle complete. 31. Batch end Emptying operation complete. Note Weighing steps 0-7 are described in Section 5.5 "Weighing steps- standard weighing procedure" of the manual "SIWAREX FTA Device Manual". The process value 1 is the current net weight and can be called from the "ProcVal1" block output. The process value 2 is the current AWI status and can be called from the "ProcVal2" block output. The current NAWI status can be called from the "ScStatus" block output. Entry ID: , V1.0, 08/

28 4 Configuring requirements Access to status bits from AWI and NAWI In both the AWI and NAWI there is a combined double word variable. These in turn form part of structural variables (consisting of value and signal status). To access the individual status bits, the structure must be first resolved. Then, a type conversion must be performed from DWORD to BIT. No direct function is provided by PCS 7 to resolve the structure. A function has to be created to resolve the structure with SCL. The "DW_DO" function can be used for the type conversion from DWORD to BIT. However, this has the disadvantage that the outputs for the individual bits have no meaningful names (Out0... Out31). For this reason, we recommend you create a function that resolves the structure and outputs the individual status bits. Meaningful names can then be assigned to the outputs. This clearly facilitates the subsequent processing of the status bits. In the present Application Example, a function has been created for both the AWI and the NAWI status. The sources can be found in the supplied example project. Note The sources for the functions that resolve the structures of the AWI and NAWI status, can be found in the supplied sample project. Figure 4-1 Function for access to status bits for AWI and NAWI status Entry ID: , V1.0, 08/

29 4 Configuring requirements 4.2 Logging of dosing operations Requirement To ensure quality, each dose should be logged with time stamp, product name, time and weight. The log should be saved in the SIWAREX FTA on a CompactFlash card. Configuring the log text In DR 4 and DR 23, it has already been defined that the output location for the protocol is the CompactFlash card and that the Text 1 should be logged (see chapter and chapter 3.3.5). Chapter 5 "Configuring of control recipe phases" describes how the selection of the log text is changed for the running period of the dosing via an SFC type instance. Configuring the log text is not possible via the function blocks of the library "SIWAREX FTA - Advanced Process Library" possible and must be performed on the PC with the SIWATOOL FTA. Note Information regarding installation and installation of the SIWATOOLS can be found in chapter 10 "Commissioning using a PC SIWATOOL FTA" of the "SIWAREX FTA Device Manual". The following describes the configuration of the texts using the SIWATOOL FTA. The texts can be configured both online and offline. In the current Application Example, the configuration is performed online. To do this, the PC must be connected to the SIWAREX FTA via the configuration cable. Table 4-3 Step 1. Open the SIWATOOL FTA. 2. Switch to the Online View. Action Entry ID: , V1.0, 08/

30 4 Configuring requirements Step Action 3. Expand the "configure" point on the left hand side of the tree view. 4. Select the point "Log text 1 (DR 40)". 5. The window "Log text 1 (DR 40)" opens up on the right hand side in the "Info" tab. Entry ID: , V1.0, 08/

31 4 Configuring requirements Step Action 6. Switch to the "Log text 1" tab and press the "Receive" button (1) The current "Log text 1" is read and displayed from the SIWAREX FTA. 7. Customize the text to suit your specifications. In the current Application Example, the text contains the following information or elements (see figure in point 6): Additional sign 1 (\F10) Date (\F0D) Time (\F0F) Additional sign 2 (\F11) Net weight in kg (\F02) In the window there is a drop-down menu (2) which allows you to insert variable text in the log text. 8. Click the "Send" button (3) to send the text to the SIWAREX FTA. Entry ID: , V1.0, 08/

32 4 Configuring requirements Step Action 9. Select the item "additional sign (DR 43)" and define the text that you want to use as an additional sign. The following additional signs are defined in the current Application Example: Additional sign 1: "Siemens:" Additional sign 2: "Component 1" Additional sign 3: "Component 2" Additional sign 4: "Component 3" 10. Click the "Send" button to send the additional signs to the SIWAREX FTA. 11. The definition of the protocol texts 2 to 4 is done in an identical way. 12. You can verify whether the protocol text has been created correctly from the point "Last log (DS 44)". For this purpose, at least one dosing has to be performed after sending the log text. To read the log, press the "Receive" button. Entry ID: , V1.0, 08/

33 4 Configuring requirements 4.3 Monitoring limit value Requirement To increase process safety, a monitoring limit value signal should be defined. On the one hand, this should be evaluated in the AS, as well as control a horn directly on site. Configuration and evaluation of the monitoring limit value Limit values are defined using the DS 4. The "Limit value 3" is particularly suitable for the monitoring limit value (up to three limit values can be defined for the SIWAREX FTA). This has already been defined as described in chapter Basic parameter (DS 4). The Limit value 3 always refers to the gross weight in the scale. The "Limit value 3" is permanently monitored. When the limit value is exceeded, it shows immediately in the NAWI status. The current value of the status bits is shown at the output Slim3On_O of the NAWI status function and can be used from there for further processing. In the Application Example, the status is switched directly to a channel block, which activates a horn. A digital output can be optionally linked to the SIWAREX module with the status of the limit value. Figure 4-2 Furthermore, the status is connected with the SFC type instance, which is used for dosing according to a recipe. If the limit value is exceeded, it is possible to perform a targeted call in the execution of the recipe structure. Entry ID: , V1.0, 08/

34 4 Configuring requirements Figure 4-3 Further functions can be realized (e.g. trigger certain message,..) with the help of the status bits. 4.4 Monitoring the dosing steps Requirement The individual steps of the doses (tare, coarse/fine signal, tolerance checking, dosing completed...) should be always monitored. Configuration The monitoring of individual dosing steps is done automatically in the SIWAREX FTA. The information about which dosing step is active, can be read in the AWI status. The individual dosing steps correspond to the status bits 0 to 7. In order to always have the current values, it is recommended to connect directly to the "ProcVal2" peripheral value. This contains the current AWI status (see chapter 0 "Interface parameters DR 7"). In the Application Example, the current values of the status bits for each dosing step are shown at the outputs "Step_0" to "Step_7" of the AWI status function. These can then be connected for further processing and evaluated in AS from the AWI status function. In this Application Example, the output "Step_0" is connected to the instance of the SFC type "Dosing" in order to check whether the dosing step 0 has been reached again after a dosing termination. Entry ID: , V1.0, 08/

35 4 Configuring requirements Figure 4-4 Note You can find information about each dosing step in Section 5.5 "Weighing stepsstandard weighing procedure" of the manual "SIWAREX FTA Device Manual". Entry ID: , V1.0, 08/

36 4 Configuring requirements 4.5 Checking the dosing for tolerance Requirement After each dosage and based on tolerance signals, it should be decided whether the dosage was "good" or not. Configuration The checking of the dosing for tolerance is performed automatically from the SIWAREX FTA. This procedure tests whether the limit values have been respected for the set tolerance bands. The test result can be read from the AW status. In order to always have the current values, it is recommended to connect directly to the "ProceVal2" peripheral value. In the Application Example, the current values of the status bits for the tolerance check are shown at the following outputs of the AWI status function: "TO2" upper tolerance limit 2 "TO1" upper tolerance limit 1 "Good" within tolerance band from "TU1" to "TO1" "TU1" lower tolerance limit 1 "TU2" lower tolerance limit 2 "TOLBad" outside of band "TU2" to "TO2" (can be used for sorting the weighing material) From the AWI status function, you can use the result of the tolerance check for further processing within the AS or display it in the OS. In the Application Example, the outputs of the AWI status function have been provided with the "S7_m_C := true " attribute. Thus, the result of the tolerance check can be visualized in the AS page of the OS without any further configuration effort. The following table describes when each state is active: Table 4-4 Condition for the status flags "TO2" "TO1" "Good" "TU1" "TU2" "TOLBad" Net weight from "TU1" to "TO1" Net weight above "TO1" to "TO2" Net weight above "TO2" Net weight from "TU2" to below "TU1" Net weight below "TU2" Entry ID: , V1.0, 08/

37 4 Configuring requirements 4.6 Optimizing the cut-off time points Requirement Configuration The scale should automatically optimize the coarse and fine signal cut-off time points for the individual components. No configuration is necessary to optimize the cut-off time points, because this is assumed automatically by the SIWAREX FTA. The controller only needs to be activated and configured in DR On site analog value display Requirement In addition, a locally preexisting analog value indicator should display the current total capacity of the scale using a 4-20 ma signal. Configuration The required configuring on the PCS 7 side has been already described in chapter 0 "Interface parameters (DR 7). All one has to do then is to connect the SIWAREX FTA module to the analog display device. Figure 4-5 Entry ID: , V1.0, 08/

38 5 Configuring the control recipe phase 5 Configuring the control recipe phase In order to achieve and automate a dosage of several components according to a recipe, an SFC type will be used in the current Application Example. The following describes a possible installation, the interfaces required by the SFC type and "SftAwi" as well as points that should be observed. 5.1 Installation of the SFC types Chains The SFC type is divided into different chains that are processed according to their starting conditions. The following chains are included in the SFC types of the sample project: "Start" "Dosing_Comp1" "Dosing_Comp2" "Dosing_Comp3" "Emptying" "Complete" "Holding" "Hold" "Resume" "Abort" Characteristics of the SFC type Control strategies The following table gives a summary of the control strategies available in the SFC type and their functions: Table 5-1 Number Name Function 1 "Comp1" Dosing of component 1 2 "Comp2" Dosing of component 2 3 "Comp3" Dosing of component 3 4 "Emptying" Empty vessel Entry ID: , V1.0, 08/

39 5 Configuring the control recipe phase Setpoints The following table gives a summary of the setpoint values available in the SFC type and their meaning: Table 5-2 Name Meaning Data record Process values "SpV" Setpoint weight for weighing 20 "InFIV_A" "FineV_A" "CompV_A" "TO1_A" "TU1_A" "TO2_A" "TU2_A" Trailing weight, quantity that keeps flowing after switching off the fine signal Fine weight, quantity that should be dosed during the fine signal Cut-off correction value, +/- additional shift of the cut-off point for the fine signal Upper tolerance limit "TO1" (amount of allowed positive deviation from the target weight) Lower tolerance limit "TU1" (amount of allowed negative deviation from the target weight) Amount of the upper tolerance limit 2 must be greater than "TO1" Amount of the lower tolerance limit 2 must be greater than "TU1" The current status and the information about the commands are read from the process values. They allow the definition of the step enabling conditions in transition. The following table gives a summary of the process values available in the SFC type and their meaning: Table 5-3 Name "ScType_O" "WStep0" "CycEnd" "EmptySig" "LCommand" "Coarse" "Fine" "CMDFOK" "Wstop" "TxtNoA_O" Meaning Currently selected control program of the scale Weighing step 0, scale is in the waiting position Weighing cycle complete Empty message, scale in empty range Last command processed Coarse signal is active Fine signal is active Automatic command complete Weighing cycle complete Currently selected log text Entry ID: , V1.0, 08/

40 5 Configuring the control recipe phase Control values The control values allow the commands to be written from the SFC type to the SIWAREX FTA module via the "SftAwi" function block. The following table gives a summary of the control values available in the SFC type and their meaning. Table 5-4 Name "WR_DR04" Write data record 4 "RD_DR04" Read data record 4 "SCTyp_M" Control program selection for scale "WR_DR20" Write data record 20 "RD_DR20" Read data record 20 "WR_DR22" Write data record 22 "RD_DR22" Read data record 22 "WR_DR23" Write data record 23 "RD_DR23" Read data record 23 "CMD100" "CMD109" "CMD118" Meaning Start weighing with Tare zeroing mode Emptying ON Emptying OFF "CMD660" Write data records 20 and 22 "CMD610" Read data records 20 and 22 "CMD651" Write data records 20 and 21 and start weighing with Tare zeroing mode "CMDFOKReset" Reset the "Automatic command complete" check "CMD105" "CMD108" "CMD103" Stop (stop immediately) in the weighing cycle, scale remains in the "stopped" state Termination, stopped weighing cycle, weighing cycle is terminated without further activities Continue, stopped weighing cycle continues "TxtNoA_M" Select log text "x" (1, 2, 3) Block contacts The block contacts allow general control commands to be read and written to the technological blocks connected with the SFC type instance. The following table gives a summary of the block contacts available in the SFC type and their meaning: Table 5-5 "ModLiOp" Name "ModLiOp_VCoarse1" Connection with SftAwi block Meaning Connection with valve block for coarse dosing of component 1 "ModLiOp_VFine1" Connection with valve block for fine dosing of component 1 Entry ID: , V1.0, 08/

41 5 Configuring the control recipe phase Name "ModLiOp_VCoarse2" Meaning Connection with valve block for coarse dosing of component 2 "ModLiOp_VFine2" Connection with valve block for fine dosing of component 2 "ModLiOp_VCoarse3" Connection with valve block for coarse dosing of component 3 "ModLiOp_VFine3" Connection with valve block for fine dosing of component 3 "ModLiOp_VEmptying" Connection with valve block for emptying of reactor Entry ID: , V1.0, 08/

42 5 Configuring the control recipe phase "START" chain The "START" chain enables the SIWAREX FTA to be switched to automatic mode and locked for the operator. The figure below shows the structure of the "START" chain: Figure 5-1 chain The figure below shows the starting conditions of the "START" chain: Figure 5-2 The following table gives a summary of the actions in single steps and the step enabling conditions in the transitions: Table 5-6 "INIT" Step/transition "Automode?" Action/step enabling condition The SIWAREX FTA is set to automatic mode at the beginning of the step processing and the operation is locked for the operator. The "CMDFOKReset" control value is additionally reset. This checks whether the SIWAREX FTA is in automatic mode. After processing the "INIT" step, the chain is completed and the appropriate Run chain is started depending on the selected control strategy. Entry ID: , V1.0, 08/

43 5 Configuring the control recipe phase "Dosing_Comp1" chain The "Dosing_Comp1" chain is used for the dosing of component 1. The corresponding setpoint values are written, the control program is specified for the scale and the appropriate valves are controlled. It tests the assumption of values and the running of commands. The "Dosing_Comp1" chain corresponds to the "Comp1" control strategy. The figure below shows the structure of the "Dosing_Comp1" chain: Figure 5-3 Entry ID: , V1.0, 08/

44 5 Configuring the control recipe phase The figure below shows the starting conditions of the "Dosing_Comp1" chain: Figure 5-4 The following table gives a summary of the actions in single steps and the step enabling conditions in the transitions: Table 5-7 Step/transition "write DR4" "Text" "Text 1?" "Dosing data DR20" "write DR20 DR22" "CMD660?" "read DR20 DR22" "CMD610?" "Valve1 C" Action/step enabling formations Selection of control program for scale via "ScType_M" control value At the beginning of the step processing, control value "WR_DR23" (write data record 23) is set to "true" and the control value "TxtNoA_M" is set to "1". During the step processing, the control value "WR_DR23" is reset. In addition, the control value "RD_DR23" (read data record 23) is set to "true". Once the step processing is completed, the control value "RD_DR23" is reset. In this way, the appropriate log text is selected. With the aid of the process value "TxtNoA_O", it checks whether the proper protocol text is selected. Dosing setpoints are assigned (see point "setpoint values" in chapter ) Command "660" (write data record 20 and data record 22) is set to "true" at the beginning of the step processing and then reset when leaving the step. By using the appropriate process values (see point "Process values" in chapter 5.1.1), it checks whether the "660" command has been correctly executed. Command "610" (read data record 20 and data record 22) is set to "true" at the beginning of the step processing and then reset when leaving the step. The control value "CMDFOKReset" is additionally reset at the beginning of the step processing and restored when completing the processing step. By using the appropriate process values, it checks whether the "610" command has been correctly executed. By using the setpoint inputs, it is also checked whether the SIWAREX FTA has received the correct setpoints. The valve for coarse dosing is put in automatic mode and receives the "Open" command from the SFC. However, it is only opened if the SIWAREX FTA also gives the command for coarse dosing. Entry ID: , V1.0, 08/

45 5 Configuring the control recipe phase Step/transition "Valve1 F" "check valves" "Dosing" Action/step enabling formations The valve for fine dosing is put in automatic mode and receives the "Open" command from the SFC. However, it is only opened if the SIWAREX FTA also gives the command for fine dosing. It checks whether the valves are in automatic mode and whether the SIWAREX is in the Weighing step 0. At the beginning of the step processing, the "CMDFOKReset" control value is reset and the "100" command (start the weighing cycle with tare) is set. When exiting the step, the "CMDFOKReset" control value is set and the "100" command is reset again. "coarse stopped?" It checks whether the last automatic command was the "100" command and whether it was carried out correctly. In addition, it also checks whether the signal for the coarse dosing of SIWAREX FTA is still active. "Valve1_C_close" "fine stopped?" "Valve1_F_close" "cycle end?" At the beginning of the step processing, the commands for automatic operation and for the opening of the valve are canceled from automatic mode. The "CMDFOKReset" control command is additionally reset. This checks whether the signal for the fine dosing of SIWAREX FTA is still active. At the beginning of the step processing, the commands for automatic operation and for the opening of the valve are canceled from automatic mode. This checks whether the SIWAREX FTA is in the "Cycle end" status. If the SIWAREX FTA is in the "Cycle end" status, the "Dosing_Comp1" chain is completed and the "Complete" chain started "Dosing_Comp2" chain The "Dosing_Comp2" chain is used for the dosing of component 2. The corresponding setpoint values are written, the control program is specified for the scale and the appropriate valves are controlled. It tests the assumption of values and the running of commands. The "Dosing_Comp2" chain corresponds to the "Comp2" control strategy. The difference between the starting conditions of the "Dosing_Comp2" chain and the starting conditions of the "Dosing_Comp1" lies only in the QCS value. For the "Dosing_Comp2" chain, this is "2". The installation and commands are nearly identical to those of the "Dosing_Comp1" chain. The only difference is in the valves, which are addressed in the individual steps and transitions, and the selected log text. If the SIWAREX FTA is in the "Cycle end" status, the "Dosing_Comp2" chain is completed and the "Complete" chain started. Entry ID: , V1.0, 08/

46 5 Configuring the control recipe phase "Dosing_Comp3" chain The "Dosing_Comp3" chain is used for the dosing of component 3. The corresponding setpoint values are written, the control program is specified for the scale and the appropriate valves are controlled. It tests the assumption of values and the running of commands. The "Dosing_Comp3" chain corresponds to the "Comp3" control strategy. The difference between the starting conditions of the "Dosing_Comp3" chain and the starting conditions of the "Dosing_Comp1" lies only in the QCS value. For the "Dosing_Comp3" chain, this is "3". The installation and commands are nearly identical to those of the "Dosing_Comp1" chain. The only difference is in the valves, which are addressed in the individual steps and transitions, and the selected log text. If the SIWAREX FTA is in the "Cycle end" status, the "Dosing_Comp3" chain is completed and the "Complete" chain started. Entry ID: , V1.0, 08/

47 5 Configuring the control recipe phase "Emptying" chain The "Emptying" chain serves for emptying the scale after all components have been dosed. The corresponding commands are sent to the SIWAREX FTA and it is asked whether the scale is in the empty range. The figure below shows the structure of the "Emptying" chain: Figure 5-5 The figure below shows the starting conditions of the "Emptying" chain: Figure 5-6 Entry ID: , V1.0, 08/

48 5 Configuring the control recipe phase The following table gives a summary of the actions in single steps and the step enabling conditions in the transitions: Table 5-8 Step/transition "WStep0" "Empt Valv Aut" "Valve in auto?" "Start Emptying" "CMD109" "Stop Empyting" "Empty?" Empt Valv Man Action/step enabling condition By using the appropriate process value, it checks whether the balance is in "Waiting position". The valve for the emptying of the scale is put in automatic mode and receives the "Open" command from the SFC. However, it is only opened if the SIWAREX FTA also gives the command for emptying. The "CMDFOKReset" control value is additionally reset. This checks whether the valve is in automatic mode. The "109" command (start emptying)is set at the beginning of the step processing. When exiting the step, the "CMDFOKReset" control value is set and the "109" command is reset again. By using the appropriate process values, it checks whether the "109" command has been correctly executed. It also checks whether the scale is in the empty range. At the beginning of the step processing, the "118" command (Complete emptying) is set and the "CMDFOKReset" control value is reset. When exiting the step, the "CMDFOKReset" control value is set and the "118" command is reset again. By using the appropriate process values, it checks whether the "118" command has been correctly executed. The valve responsible for emptying is released again for the operator via the corresponding block contacts. The "CMDFOKReset" control value is additionally set. Once the chain has been completed, the "Complete" chain is automatically started. Entry ID: , V1.0, 08/

49 5 Configuring the control recipe phase "Complete" chain The "Complete" chain is run at the end of the SFC processing. It releases the SIWAREX FTA again for use by an operator via the OS faceplate. The figure below shows the structure of the "Complete" chain: Figure 5-7 The figure below shows the starting conditions of the "Complete" chain: Figure 5-8 The following table gives a summary of the actions in single steps and the step enabling conditions in the transitions: Table 5-9 Step/transitions "Manual mode" Action/step enabling condition The values of the block contacts "ModLiOp_AutModLi.Value" and "ModLiOp_ModLiOp.Value" are reset. After the chain completes, the SFC goes in the "IDLE" status, and can then be restarted for a new dosing/emptying. Entry ID: , V1.0, 08/

50 5 Configuring the control recipe phase "HOLDING" chain The "HOLDING" chain is started as soon as a Run chain is stopped, for example, to stop the dosage, or the emptying. The "HOLDING" chain moves the SFC from the "Run" state (running) to the "Hold" state (stopped). While the "HOLDING" chain is active, the SFC is in the "Holding" state (persistent). The figure below shows the structure of the "HOLDING" chain: Figure 5-9 The figure below shows the starting conditions of the "HOLDING" chain: Figure 5-10 Entry ID: , V1.0, 08/

51 5 Configuring the control recipe phase The following table gives a summary of the actions in single steps and the step enabling conditions in the transitions: Table 5-10 Step/transition "Stop" "CMD105?" "HOLD" Action/step enabling condition Command "105" (Stop, stop immediately) is set to "true" at the beginning of the step processing and then reset when leaving the step. When exiting the step, the "CMDFOKReset" control value is set to "true". By using the appropriate process values, it checks whether the "105" command has been correctly executed. It also checks whether the scale is in step 0 (waiting). When exiting the step, HOLD is set to the "Hold" value. Once the "HOLDING" chain has completed, the SFC switches to the "HOLD" chain "HOLD" chain The "HOLD" chain is started as soon as the "HOLDING" chain is exited. The "HOLD" chain remains active until the starting condition of the "RESUME" or "ABORT" chains is activated. The figure below shows the structure of the "HOLD" chain: Figure 5-11 Entry ID: , V1.0, 08/

52 5 Configuring the control recipe phase The figure below shows the starting conditions of the "HOLD" chain: Figure 5-12 The following table gives a summary of the actions in single steps and the step enabling conditions in the transitions: Table 5-11 Step/transition "HOLD = 0" Action/step enabling condition At the beginning of the step processing the value HOLD is set to "false". "leave seq?" This checks whether one of the conditions "RESUMING = Resuming", "STOPPING = Stopping" or "ABORTING = Aborting" is fulfilled. After the "HOLD" chain has been completed, the SFC switches to the "RESUME" or "ABORT" chain, depending on the condition which was satisfied in the "leave seq?" "RESUME" chain The "RESUME" chain is started as soon as the "HOLD" chain is processed and the starting condition "RESUMING = Resuming" is available. The "RESUME" chain enables the dosing or emptying to continue. The figure below shows the structure of the "RESUME" chain: Figure 5-13 Entry ID: , V1.0, 08/

53 5 Configuring the control recipe phase The figure below shows the starting conditions of the "RESUME" chain: Figure 5-14 The following table gives a summary of the actions in single steps and the step enabling conditions in the transitions: Table 5-12 Step/transition "Resume" "CMD103?" Action/step enabling condition At the beginning of the step processing, the "CMDFOKReset" control value is reset and the "103" command (continue) is set to "true". When exiting the step, the "CMDFOKReset" is set to "true" and the "103" command is reset. By using the appropriate process values, it checks whether the "103" command has been correctly executed. It also checks whether the SIWAREX FTA has exited the Weighing step 0. After the "RESUME" chain has been completed, the process of the previously interrupted chain is resumed. Entry ID: , V1.0, 08/

54 5 Configuring the control recipe phase "ABORT" chain The "ABORT" chain is started as soon as the "HOLD" chain is processed and one of the starting conditions "ABORTING = Aborting" or "STOPPING = Stopping" is present or when the SFC is aborted immediately. The "ABORTING" chain causes the dosing or emptying to abort. The figure below shows the structure of the "ABORT" chain: Figure 5-15 The figure below shows the starting conditions of the "ABORT" chain: Figure 5-16 Entry ID: , V1.0, 08/

55 5 Configuring the control recipe phase The following table gives a summary of the actions in single steps and the step enabling conditions in the transitions: Table 5-13 Step/transition "STOP" "CMD105?" "ABORT" CMD108? Action/step enabling condition At the beginning of the step processing, the "105" command (stop, stop immediately) is set to "true" and the "CMDFOKReset" control value is reset. When exiting the step, the "CMDFOKReset" is set to "true" and the "105" command is reset. By using the appropriate process values, it checks whether the "105" command has been correctly executed. It also checks whether the scale is in the "stopped" range. At the beginning of the step processing, the "108" command (abort) is set and the "CMDFOKReset" control value is reset. When exiting the step, the SIWAREX FTA and the valves for components 1, 2, and 3 as well as the emptying valve are released again for the operator ("ModLiOp" = "0"). The "108" command is also reset and the "CMDFOKReset" control value is set to "true". By using the appropriate process values, it checks whether the "108" command has been correctly executed. It also checks whether the scale has returned to Weighing step 0. Note The step "STOP" is required by the chain to bring the weighing cycle in the "stopped" state. An abortion of dosing or emptying is only possible from this state. Once the "ABORT" chain has completed, the "complete" chain is started and the SFC is set to the state "IDLE", and can be restarted. Entry ID: , V1.0, 08/

56 5 Configuring the control recipe phase Additional configurations required In oder to enable the control and process values to write or read between the SFC type instance and "SftAwi" FB, a data type conversion is required for certain values. Furthermore, a buffer for this value is required in order to test whether the last command has been executed correctly. Controller operating mode The operating mode of the scale is defined at input "ScType_M" of "SftAwi" FB. This belongs to the "BYTE" data type. The control value "ScType_M" with the data type "INTEGER" is used at the SFC type for this purpose. In order to enable the writing of the control value to the SIWAREX FTA, one must first convert the data type from INTEGER to BYTE. The "Convert" blocks provided by PCS 7 can be used for this purpose. The figure below describes the structure of the type conversion: Figure 5-17 The conversion takes place in the CFC chart, where the "SftAwi FB" has also been inserted. For checking purposes via the SFC type (have the values been taken over correctly from the SIWAREX FTA?), the type conversion is also performed in the reverse direction. Log text selection The log text that should be used for logging, is defined at the "TxtNoA_M" input of the "SftAwi" block. This belongs to the "BYTE" data type. The control value "TxtNoA_M" with the data type "INTEGER" is used at the SFC type for this purpose. In order to enable the writing of the control value to the SIWAREX FTA, one must first convert the data type from INTEGER to BYTE. The "Convert" blocks provided by PCS 7 can be used for this purpose. Entry ID: , V1.0, 08/

57 5 Configuring the control recipe phase The figure below describes the structure of the type conversion: Figure 5-18 The conversion takes place in the CFC chart, where the "SftAwi" block has also been inserted. For checking purposes via the SFC type (have the values been taken over correctly from the SIWAREX FTA?), the type conversion is also performed in the reverse direction. Checking the last command In the transitions of the SFC type, it is checked whether the last command has been executed correctly. This information can be read at output "CmdFOK" of the "SftAwi" block. In order for the information to be processed properly in the SFC type, it must be buffered with the aid of a FlipFlop. The FlipFlop is reset by the SFC type after the evaluation takes place and restored at the next correctly executed command until it is reset again by the SFC type after the evaluation. The figure below describes the structure of the logic: Figure 5-19 Entry ID: , V1.0, 08/