question
stringlengths 19
6.88k
| answer
stringlengths 38
33.3k
|
|---|---|
Problem Statement: Have there been any changes to the reports in V7.3?
|
Solution: The default value for the report output format changed in v7.3 CP3 from 'TEXT' (or 'CSV') to 'XML'.
Below are the calling arguments. All are optional except the report name and have default values.
PROCEDURE AW_CUSTOM_DATA(Arg_REPORTNAME CHAR(24), Arg_ENDTIMESTR CHAR(24) = '',
Arg_HISTTYPE CHAR(8) = '', Arg_DELTA INTEGER = 1, OUTPUTTYPE CHAR(4)='XML',
WEBURL CHAR(256)='', LANGOPT CHAR(2)='EN', Arg_APPNAME CHAR(24)='')
To generate the original report format, make sure you specify the OUTPUTTYPE argument as 'TEXT' or 'CSV' (both give the same result). The other options for this argument are 'XML' (default) and 'HTML'.
Keywords:
References: None
|
Problem Statement: How do you generate separate custom reports for each sub-controller with only specific MVs and CVs selected?
|
Solution: The following information is also available in the attached word document which details the procedure for setting up separate custom reports for each sub-controller while selecting only specific MVs and CVs.
Such custom reports can be generated by creating dummy custom KPIs for each of the variables you need in the report, setting them to a constant value and then using the filter option in the custom report generation window to filter out the unnecessary MVs and CVs. The steps below illustrate the procedure to set up a custom report for a particular sub-controller using an example controller application running using data from a virtual plant simulation on Aspen Hysys.
The procedure below sets up a custom report using select MVs only (FC-D3TOPSP and PC-D3OVHDSP) for subcontroller DC2 in the example HGP controller.
MVs in DC2- TC-F1OUTSP, PC-D3OVHDSP, FC-D3TOPSP, TC-D3BTMSP, PC-T1OVHDSP
1. Open AspenWatch and navigate to Tools|Custom Calculations? to open up the ?Custom Calculations? window.
2. Click the ?New? button on the bottom of the screen to bring up the ?Custom Calculation Configuration? window.
3. Set the appropriate parameters as shown in the screenshot below-
4. Note that the Alarm type is configured as ?Event.? Also note the formula used for the calculation. Since AW does not allow a constant number for a formula, you will need to enter some equation using Variable Binding. This example uses a logical if statement to check if the ?Anti-Windup Flag? for the variable is equal to 2. Whatever be the value of the Anti-Windup status, the calculation will always equal a value of 2 because of how the if-function is written.
5. Once you click save, you will be asked if you want to duplicate this calculation for other variables. Click yes, and select all variables (belonging to the same subcontroller) you want to duplicate this calculation for. In this case, the calculation is duplicated for variable PC-D3OVHDSP. Also duplicate the custom calculation for the other variables in the list, but make sure to change the Formula to set the calculation to a different value (see Step 13). Note the highlighted calculations in the screenshot below-
6. Close this window and proceed to Tools|Report Management on the AspenWatch window.
7. Click ?New? to configure a new report and fill in the necessary information in the ?Report Configuration? window that shows up.
8. Click the ?New? button in the ?Report Sections? region to open up the ?Define Report Section? screen. Enter the appropriate information you want in the report, including the dummy custom calculation we created in Steps 3 to 5. See example below-
9. Note that you need to select the dummy custom calculation as the ?Sort Column? in Filter Options, select the ?Eliminate Rows? check-box, select ?Not Equal To? from the dropdown list and set the value of the threshold to 2 because that is the value we set the dummy calculations to in the previous steps.
10. Select the ?Save? button to save the configuration.
11. Switch to the WebViewer/PCWS to test out this custom report. The screenshot below shows the report that is generated for the HGP example-
12. You can also set up custom calculations for CVs to be included in the report in a similar manner.
13. For generating a custom report for a different subcontroller, use the same technique as listed above but make sure to use a different value for the custom calculation (TESTMV1 in this example) in the formula option. Set the custom calculation to 0 (ZERO) for all variables that you do not want to include in the custom report. Refer to table below as an example of custom calculations for independent variables-
Subcontroller (SC) #
Formula
X
1
@IF(X = 1, 1, 1)
Some parameter in the MVs in the controller
2
@IF(X = 1, 2, 2)
Same parameter as used for MV in SC#1
3
@IF(X = 1, 3, 3)
Same parameter as used for MV in SC#1
For variables in any/all subcontroller that you do not want included in the report
@IF(X = 1, 0, 0)
Same parameter as used for MV in SC#1
For example, if you used the Anti-Windup status as X for configuring the custom calculations for variables in SC#1, duplicate the calculation for the variables in the other subcontroller and change the ?Formula? as shown above.
Keywords: AspenWatch Maker
Custom Reports
Sub-controllers
Specific variables
References: None
|
Problem Statement: I have installed DMCplus on-line 2004 as well as Aspen Dynamics 2004 on my computer. I have copied the dmcplus files released with the example in the correct location (c:\program files\aspentech\ac online\app\MCHCOL)
I get the following messages when I run in AD the example MchDMCplus.dynf.
Integrating from 0 to 0.01
Restarting integrator at 0
...
DMCplus Interface: Initializing link to controller MCHCOL
DMCplus Interface: Initialization complete
Step 1: Time = 0.005, step = 0.005 rejected, error/tol = 2.8874 Step 2: Time = 0.0016814, step = 0.0016814 accepted, error/tol = 0.39432 Step 3: Time = 0.0033814, step = 0.0017 accepted, error/tol = 0.2266 Step 4: Time = 0.0056485, step = 0.0022672 accepted, error/tol = 0.3787 Step 5: Time = 0.0079875, step = 0.002339 accepted, error/tol = 0.27305 Step 6: Time = 0.010829, step = 0.0028417 accepted, error/tol = 0.32727 Integrating from 0.01 to 0.02
Step 7: Time = 0.013983, step = 0.0031537 accepted, error/tol = 0.39885
Step 8: Time = 0.017153, step = 0.0031703 accepted, error/tol = 0.43185
DMCplus Interface: Error running DMCplus controller
Step 9: Time = 0.020007, step = 0.0028533 accepted, error/tol = 0.35213 Step change at 0.02 activated
Integrating from 0.02 to 0.03
Restarting integrator at 0.02
DMCplus Interface: Error running DMCplus controller
Step 10: Time = 0.025, step = 0.005 rejected, error/tol = 1.8574 DMCplus Interface: Error running DMCplus controller
Step 11: Time = 0.022096, step = 0.0020964 accepted, error/tol = 0.10551 etc...
Why do I get these messages:
DMCplus Interface: Error running DMCplus controller
Apparently the simulation is still running correctly.
|
Solution: These error messages indicate a time out from the controller at the start of the run.
We recommend setting the controller MCTOL parameter to -1 to switch of missed cycle checking. For version 2006, we have changed the mchcol.ccf file that we deliver to use this value.
When configuring the Controller in DMCplus, please note the following recommendations. Because the simulation schedules execution of the controller you must ensure that the WTMODE entry for the controller is set to a value of 2. It is also recommended that you set the missed cycle tolerance, MCTOL to a value of -1 to avoid missed cycle checking error messages. If you do not do this you may see some error messages from the controller at the start of the simulation, although the simulation will run OK.
These comments will also be added to the on-line help for version 2006.
Keywords:
References: None
|
Problem Statement:
|
Solution: This Windows help file is divided into five books:
Introduction
Symptoms
Problems
Diagnostics
Actions
The Symptoms book contains pages for various symptoms of problems that Aspen Watch users sometimes encounter. For each symptom, links may be provided to potential problem descriptions or diagnostic tools or techniques.
The Problems book contains descriptions of potential problems andSolutions.
The Diagnostics book contains descriptions of tools or techniques that can be used to diagnose problems.
The Actions book gives instructions for performing certain tasks that are used to solve or diagnose problems.
Earlier versions of this help file were distributed on the Aspen Watch 1.1.0 and 1.2.0 installation CDs.
Installation & Use
The AWTroubleshooting.zip file contains the following files:
AWTroubleshooting.hlp - help file
AWTroubleshooting.cnt - table of contents file
Roboex32.dll - supports WinHelp 2000 features
Simply extract the files to a folder of your choice and double-click AWTroubleshooting.hlp to start using the help file. You may not need Roboex32.dll if it is already on your system.
This application tool has not been reviewed by Aspen Technology's Quality Assurance group, and it it not part of the Aspen Watch product; therefore, it is not officially supported by AspenTech.
Keywords: AppTool
References: None
|
Problem Statement: Why do I get the error Run-time error '429': ActiveX Component can't create object, when trying to start up Aspen Watch Maker?
|
Solution: There are certain libraries that are shared with Aspen Watch Maker and other products. If you have in the server DMCplus Build, DMCplus Model, DMCplus Simulate or IQConfig and you try to open it do you have the same error?
This type of run-time messages points that a library is not well register. The most common one is STRGXI2.DLL please follow the steps fromSolution 111596 and register the STRGXI2.DLL
If this does not solve the problem here are the DLLs that AWMaker accesses. Regsvr32 can be used to re-register them if needed. Some may not need to be registered and will give and error. But that is normal.
Library
Description
SLM Common Error Dialog.dll
SLM Common Error Dialog
AMSUtils.dll
AMSUtils Module
AtDsaLocator.dll
ADSA Locator Component
AWMaker.exe
Configuration tool for Aspen Watch
Dynfrmlapi.dll
Formula API Dynamic Link Library
ip21odbc.dll
SQLplus ODBC Driver
libc21.dll
Database.21, Application
STRGXI2.dll
STGRXI2 Module
Keywords: ActiveX
Aspen Watch Maker
DMCplus Build
DMCplus Model
DMCplus Simulate
IQConfig
References: None
|
Problem Statement:
|
Solution: This SQLplus query extracts data from Aspen Watch history and writes it to a text file. Data collection can be done in a piecemeal fashion. For example, the query can be set up to extract 24 one-hour averages during each query execution for 365 executions, thereby extracting a year's worth of one-hour averages a bit at a time. This is accomplished by storing the query in an InfoPlus.21 QueryDef record and using the RESCHEDULE_INTERVAL to specify the time between query executions. The name of the record containing the query is used to determine the names of the input and output files.
Installation & Use
See StepExtract.pdf for detailed instructions.
This application tool has not been reviewed by Aspen Technology's Quality Assurance group, and it it not part of the Aspen Watch product; therefore, it is not officially supported by AspenTech.
Keywords: AppTool
References: None
|
Problem Statement: How do you configure valve dynamics? What are the different equations used in valve dynamic modeling?
|
Solution: In Aspen Plus Dynamics one can configure valve dynamics depending on the process condition and type of valve in question. Valve dynamics can be based on zero order, 1st order, or 2nd order dynamic action.
1) Zero order dynamics valve is a direct action valve and is available to select if no dynamics are involved in valve opening.
2) Following 1st order dynamic equations are used:
3) Following second order dynamics equations are used:
When velocity limiting is used, the rate of change of stem position is clipped so that it does not exceed the maximum velocity defined by the stroke time. One can configure valve dynamics by going to Form || Configure valve Dynamics and selecting the dynamics type. Relief valve dynamics ( PSV2) are governed by 2nd order dynamics. Valve dynamics can be controlled by adjusting time constant via manipulating Hookes constant. Default Hookes constant for the valve model is 1E5 N/m whereas, in the relief valve model, it is about 5 E5 N/m. By lowering the time constant, relief valve dynamics can be made significantly faster. In the actual relief valve model code (PSV2), constant 10000 in the 2nd order dynamics is a safety factor for possible scaling problem. When a dynamic change is too small (but still moving), it amplifies the difference between positions, therefore it could be address difficult numerical situation better. You can change the value, it won't affect the result, but it could affect computational performance.
Keywords: Valve Dynamics, Stroke time, Relief valve
References: None
|
Problem Statement: I want to see file XYZ on my Aspen Watch server, but it is located in another building and I don't have access to it. This is a downside of working in a client/server environment. Client/server software has its advantages. It's what allows us to view trends of data located on a computer in a different room, a different building or different state. However, it can be frustrating when we want to view or modify a file on the server and it is not located in a shared folder for which we have permissions. SQLplus has two powerful features to help relieve the frustration.
|
Solution: The first is the SYSTEM statement. The SYSTEM statement executes an operating system command. In the case of Windows NT, the SYSTEM statement can execute any command that can be entered at the Windows NT Command Prompt. The operating system command executes on the server computer; therefore, if I run the following query
SYSTEM 'dir c:\';
from the SQLplus Query Writer on my client computer, the result will be a listing of the C drive on the server computer. The server on which the query will execute can be set by selecting Query | Host? from the menu in SQLplus Query Writer. Obviously, I can delete files, rename files or move files to a different folder on the server computer. But what if I want to copy a folder from the server computer to my client computer? This is where the next feature comes in handy.
SQLplus supports Uniform Naming Convention (UNC) names. If your client computer (or any other computer on the network for that matter) is named CLIENT1 and it has a folder, D:\MyFiles\MyVulnerableFiles\, that is shared (with appropriate permissions) as Public, then you can access any folders or files under MyVulnerableFiles with the following path
\\CLIENT1\Public\
In order to use a UNC path in SQLplus, the permissions on the shared folder must give access to the account that was used to start InfoPlus.21 on the server computer. Giving full access to Everyone is one way to ensure that SQLplus will have access.
A sample query, which takes advantage of these two features, is attached. A nicely formated version of this text in MS WORD format is also attached <--- This should be changed to PDF format for Customer Access
This application tool has not been reviewed by Aspen Technology's Quality Assurance group, and it it not part of the Aspen Watch product; therefore, it is not officially supported by AspenTech.
Keywords: AppTool
References: None
|
Problem Statement: Maker generates a Controller is already loaded error when trying to load a new controller.
Details: This error can occur if the CCF was created using DMCplus Build 2.0 or later AND there are continuation lines in the CALC section that contain one of the following text patterns starting in the second character on the line: IND:, DEP: or SUB:.
|
Solution: Update the SQL stored procedures that handle the creation and updating of DMCplus controller records in the Aspen Watch database. Use the following procedure:
Copy the attached files onto your Aspen Watch Server machine.
Make sure InfoPlus.21 is running.
Run the SQLplus query writer and open the AWP_CREATE_RECS.SQL file.
Choose the Record | Save As menu option. In the resulting dialog change the record name from AWP_CREATE_RECS.SQL to AWP_CREATE_RECS and click the Save button. You should get a message asking if it is OK to overwrite the existing record. Click the Yes button.
Now open the AWP_UPDATE_RECS.SQL file.
Choose the Record | Save As menu option. In the resulting dialog change the record name from AWP_UPDATE_RECS.SQL to AWP_UPDATE_RECS and click the Save button. You should get a message asking if it is OK to overwrite the existing record. Click the Yes button.
You're done. Using Maker, delete any controllers that may have generated the original error, and then load those controllers again. The error should not occur.
Keywords:
References: None
|
Problem Statement:
|
Solution: FindBadDMCpLimits.sql is an SQLplus query that can identify inconsistent DMCplus limits. For each DMCplus manipulated and controlled variable, the following calculations are made:
Lower Engineering Limit - Lower Validity Limit
Lower Operator Limit - Lower Engineering Limit
Upper Engineering Limit - Upper Operator Limit
Upper Validity Limit - Upper Engineering Limit
Upper Operator Limit - Lower Operator Limit Obviously, if the limits are consistent, the results of all these calculations are positive. If one of the calculations yields a negative result, the variable and all its associated calculation results are output. No output is made for variables that have consistent limits.
Installation & Use
Open in SQLplus (Query Writer) and execute.
This application tool has not been reviewed by Aspen Technology's Quality Assurance group, and it it not part of the Aspen Watch product; therefore, it is not officially supported by AspenTech.
Keywords: AppTool
References: None
|
Problem Statement: Upgrade an Aspen Watch 2.x to 2.2 without upgrading IP21 as required with ACS 3.1 distribution package.
|
Solution: Here are the files needed to upgrade a Aspen Watch 2.0 or 2.1 system (AMS 3.0 or 3.1) to a pseudo- 2.2 system (AMS 4.0). It fixes a number of problems.
As with all activities with IP.21, first save a database snapshot to a name you'll recognize just in case something goes wrong. Also, when updating various files, save a copy of them just in case.
Part A) The files in the following ZIP file (AWcfgFiles.zip) should all replace the ones in your %ASPENWATCH%\etc\cfg folder. Once you copy these files in place, make sure IP.21 is running and then use the Install Database Configuration Start menu command (under Aspen Watch). Follow the on-screen instructions and then re-start IP.21 when finished. Then proceed to apply the next zip file's contents (Part B)...
Part B) The files in the next zip file (AW221Fixes.zip) should be applied as follows: Start with IP.21 running...
For the two SQL files, just load them using SQLplus query writer Record->Save As menu option and be sure to remove the trailing .SQL from the record name (it should tell you the record already exists when the name is correct; select Yes to overwrite it).
Shutdown IP.21 before applying the rest of the files
The rest of the files go in the following locations:
AWCollect.exe, DMCWatch.exe and AWEvents.dll (...Program FIles\AspenTech\Aspen Watch folder) PIDWatch.exe (...Program Files\AspenTech\InfoPlus.21\db21\code folder)
Now re-start IP.21 and you're done.
Keywords: AspenWatch, upgrade, IP21, 2.2
References: None
|
Problem Statement: Multiply block in the Control models library will not give the correct results. This is observed when a user is using Units of Measure (UOM) that is not Metric.
|
Solution: Internally the Aspen Dynamics library performs the calculations in Metric units. The multiplier block is actually converting the signal to metric units and then applying the multiplication factor. This is true for all the models in the Dynamics library.
Keywords: Dynamics library, Units of Measure, Multiplier, Metric
References: None
|
Problem Statement: 在 Aspen Process Explorer 中，所有位号的值都出现 Query completed with errors 错误信息。此错误发生在安装了 Aspen Process Explorer 的机器上，原因是因为下载了比 Aspen Process Explorer 版本还新的 Aspen IP.21 Process Browser (老版本称为 Aspen Web.21) 的组件。
|
Solution: 升级 Aspen Process Explorer 版本并保持和下载的 Aspen IP.21 Process Browser 组件版本一致或者重新安装 Aspen Process Explorer。Aspen Process Explorer 和 Aspen IP.21 Process Browser 客户端的版本必须要保持一致以便正常运作。
注: 根据 V7.1 Aspen IP.21 Process Browser (Web.21) 安装手册 (Chapter 2), 提到如下内容：
不要在安装了旧版本的 Aspen Process Explorer 的机器上下载最新版本的 Aspen IP.21 Process Browser 客户端。这样会导致 Aspen Process Explorer 的趋势图不能正常显示。
Keywords: query, editor
References: None
|
Problem Statement: How can I change a pressure driven simulation to a flow driven simulation within Aspen Plus Dynamics?
|
Solution: It must be noted that the pressure driven and flow driven simulations require different fixed variables. In the pressure driven mode the feed and product stream pressures are fixed and the flowrates for the interal streams are calculated and it is declared as a free variable. In the flow driven simulation mode the inlet feed is also fixed.
The first step in the change of simulation mode is done in the all Globals Table. The parameter GlobalPDriven should be made to be false as shown below.
The flowrate for the inlet feed stream should then be set to be a fixed variable under the 'Spec' Options column as shown below:
The specifications can be compared with the original pressure driven specs as show below:
Finally, the pressure for the product stream should be made a free variable. In the attached files, there are two example showing the different simulation modes.
Keywords: , pressure driven, flow driven, AllGlobals
References: None
|
Problem Statement: Can AspenWatch differentiate between controllers that are named the same but on different DMCplus systems?
|
Solution: No. Aspen Watch requires a unique folder name to store data files for each application. So it is not possible to monitor two controllers with the same name on a single Aspen Watch server.
Keywords:
References: None
|
Problem Statement: Load a SmartStep tester, and get validation error. Everything seems to be OK, but it isn't working.
|
Solution: Frequently the user will identify the logical device for the DMCplus context server instead of the SmartStep context server. Make sure you are using the logical device specified for the SmartStep context server, usually IOSMST.
Keywords: SmartStep
Tester
Validation Error
References: None
|
Problem Statement: Aspen Watch database upgrade procedure is not documented. Such as creating base database or usage of oktomodify.aw.
|
Solution: Aspen Watch Database upgrade procudure
1. Restore Group Configuration file
2. Copy following Aspen Watch files into IP.21 folders
...\AspenTech\Aspen Watch\etc\cfg\oktomodify.aw, Old Aspen Watch Snapshot file ->
...AspenTech\InfoPlus.21\db21\group200
...\AspenTech\Aspen Watch\etc\cfg\AW_Defs.RLD, AW_Recs.RLD ->
...AspenTech\InfoPlus.21\db21\etc
3. Start InfoPlus.21 Manager and select Actions -> Upgrade Database
And InfoPlus.21 Database Upgrade Wizard is invoked.
4. Enter old Aspen Watch snapshot file name into Snapshot filename box. And, press Next button
5. Select Build and load a new snapshot and push Next button.
5. Add AW_Defs and AW_Recs and press Next
6. Select Modify some records and enter oktomodify.aw into the upgrade Options box and push Finish button.
5. Enter new snapshot name into save database as box.
Keywords: oktomodify.aw, AW_Defs.RLD, AW_Recs.RLD
References: None
|
Problem Statement: How to get Aspen Watch data into Excel
|
Solution: Look in Process Data Add-in Help (in Excel, click Aspen || Process data || hlp. Then under the major heading Using the Process Data Add-in, and the sub section?Defining Map Information for Tags it tells how to get the data using AtMapDef records.
A possible query:
select name, map_definitionrecord, map_currentvalue from atmapdef where map_definitionrecord='aw_piddef'
to see which map records pertained to AW_PIDDef. The map records that pertain to PV, OP, and SP data are:
AW_PV_M
AW_OP_M
AW_SP_M
Following the instructions, I put the tagname in one cell, the map record in the third cell over as follows:
Then selecting a cell where I want the ?vector? data to start, I click on ?Aspen || Process Data || Get Data || Trend/Aggregate Data?, and get the following dialog:
Now, I highlight the cells containing the tag, (optional server name not in my example), and map record name, I find it automatically placed in the ?tags? box in the dialog.
Now, select the other parts you want, like type (I chose ?actual?), and time window. You may need to change ?Max. Number of points:?, I accepted the default, etc.
Click the ?Settings?? button to get the following dialog. This is by default, but you may want rows across, and if you have more than one server, you may need to choose.
In the second tab (output) if you want the time, you will need to select it, the default is value. .
When the final OK is clicked you get the following.
The ##### means the column is not wide enough, expand to see the contents.
Keywords: excel, aspenwatch, data
References: None
|
Problem Statement: I have chosen different communication intervals along a dynamic run so I can view the history of variables through the process when it changes faster (smaller communication interval chosen) and slower (larger communication interval). However, when I look at the history table, I find that the interval reported is different from what has been chosen by me.
|
Solution: During the run, data is requested from the simulation server at the specified communication intervals. So it is important to select the correct communication interval in order not to miss the changes as you view the plot during the run. The history table corresponding to the plot is only updated when there are changes in the values above a certain tolerance. At the end the table is generated by default for the current communication interval. The communication interval is a system value that can be changed during the run and the current value, at the end of the run, will be used. Hence you will see at the end of the run the history table using the same communication interval to calculate the points, rather than a varying value as was used through the run.
You can change the points interval to be reported at the end of the run by simply right mouse clicking the history table and choosing properties. Go to History time Settings tab and un-tick use communication interval. Then you can enter your own value in the Time interval field and the history table will be re-populated with the new interval. The key factor is that you can only have one interval throughout the whole table, but you can make it as detailed or not as you wish. The values reported will be interpolated from the values actually available from the server.
If you would like to use a script, say in automation, to transfer all data to Excel for instance, you can use the History method at the end of the run. You can set different intervals and different reporting intervals for each, e.g.:
set hist1 = Blocks(B1).stage(1).T.history (0, 1, 0.1)
set hist2 = Blocks(B1).stage(1).T.history (1, 2, 0.01)
Etc.
The above will return the history collection for the variable at different times and for different intervals. You can create a script to get that information onto a file or another application, or simply on the simulation messages window.
Keywords:
References: None
|
Problem Statement: Message: AW Events Database should be archived and events deleted
|
Solution: Message: AW Events Database should be archived and events deleted
This is an automatic response to the fact that there are more than 20,000 events in the AWEvents database. It is also a good reminder that some maintenance should be done to the AWEvents database.
There is a routine (AWEventMaintain) which, if scheduled, will perform periodic clean-up of the AWEVents database. It will delete obsolete, redundant, or superfluous events from the database. This will reduce the number of events in the database, but it will not reduce the actual size of the AWEvents.mdb file. To reduce the size of the file, you must use the compact, or compact and repair functions of either MSAccess or an Access Application Object to recover the space previously occupied by deleted events.
Make sure AWEventMaintain is scheduled: In IP.21 Administrator, go to Definition Records/QueryDef/AWEventMaintain and make sure that #SCHEDULE_TIMES is non-zero. 1 is sufficient. Now expand AWEventMaintain and select the #SCHEDULE_TIMES repeat area. In the RESCHEDULE_INTERVAL field, enter the reschedule interval. This is how frequently you want the cleanup routine to run. Probably somewhere between once an hour (+00001:00:00.0) or once a day (+00024:00:00.0) is a good guess. Once the RESCHEDULE_INTERVAL is filled in, the SCHEDULE_TIME can be entered. (SCHEDULE_TIME is entered before RESCHEDULE_INTERVAL is defined, the record will be activated ONCE and then the SCHEDULE_TIME will be written back to undefined (???????)) When entering the SCHEDULE_TIME, it might be advisable to consider the times when the database is busiest, and insure that it is scheduled some other time, if that's possible. #OUTPUT_LINES can be set to a positive value (10 to 20) and any informational output, or error messages can then be written to the #OUTPUT_LINES repeat area. The non-zero #OUTPUT_LINES is optional. Without it, no information or error messages will be written, but it's absence will not impede the execution of the query.
Compact the AWEvents.mdb database: If MSAccess is installed on your computer, Stop IP.21/AspenWatch, then double-click on the AWEvents.mdb file in ...AspenWatch\data directory. This will bring up the AWEvents database in MSAccess. In MSAccess, go to tools/Database Utilities/Compact and Repair database... and follow the instructions. Some points: The compact function in Access will write the new compacted database to a new file, and you will be required to switch file names until the new database is named AWEvents.mdb. If you use another compact method, consider if your level of risk without copying your database to a protected file name is acceptable. If not, make a copy. Also, it's possible you may try to compact an Access 97 database using Access 2000. Access will prompt you to convert your database to the new format before it can proceed with the maintenance. It is OK to do this. AspenWatch will work with either format. If you have a newer version of AspenWatch that has an Access 2000 database, and you have Access 97 installed, you must either upgrade to Access 2000, or use another method. Access 97 will not open an Access 2000 database.
If you do not have MSAccess installed, or you have a problem with version incompatibility, Stop the IP.21/AspenWatch database and run a VB script written to call the CompactDatabase function of the appropriate DAO object. If you have AspenWatch from AMS 5.0 SP1 or later, then you're probably not reading this, because the VB script is distributed with AspenWatch and executed at the end of the AW_CleanAWEvents procedure (which is called by AWEventMaintain). If you have a prior version, this VB Script is available from AspenTech Support.
Keywords: Aspen Watch, Watch, Events, Events Database, AW, archive
References: None
|
Problem Statement:
|
Solution: The DetectOffSpec SQLplus query utility was designed to do the following:
identify periods of time when a feed rate or product rate was abnormally low
identify periods of time when a key process variable was violating some limit. The algorithm is fairly generic, so it might have other applications as well.
Basically, the utility detects periods of time when a parameter has violated a limit. We say that the parameter is off spec during these periods. The parameter can be any DMCplus parameter, miscellaneous tag value or PID loop parameter in the Aspen Watch/IP.21 database (we will refer these parameters as tags). The tag limit can be specified by the user, read from the database or calculated based on a running average of the tag's value. The limit can be biased to account for noise. It is possible to specify a minimum amount of time that the tag must be off spec before the off spec condition is reported. For the case where the limit is calculated based on the tag's running average, it is possible to specify a maximum time interval after which the tag is considered to be back on spec and the limit is reset to the current average.
The OffSpecStats SQLplus query utility adds the following statistics to the output generated by DetectOffSpec.sql.
The various statistics in the report are:
Maximum - the maximum value for the tag during the off spec period
Minimum - the minimum value for the tag during the off spec period
Average = the average value for the tag during the off spec period
Ideal - an estimate of what the average value would have been if the off spec/upset condition had not occurred
Loss = (Ideal-Average) * Duration of off spec period
DetectOffSpec.zip (attached) contains the following files:
DetectOffSpec.pdf - user notes for the DetectOffSpec and OffSpecStats utilities
DetectOffSpec.sql - DetectOffSpec utility
OffSpecStats.sql - OffSpecStats utility
AW_Sec2DeltaString - Converts seconds into a delta-time string with format +HH:MI.
Installation & Use
DetectOffSpec.pdf describes how to use the utilities.
This application tool has not been reviewed by Aspen Technology's Quality Assurance group, and it it not part of the Aspen Watch product; therefore, it is not officially supported by AspenTech.
Keywords: AppTool
References: None
|
Problem Statement: When running Install Database Configuration for version 2006, it fails when loading records from IP21Health.rld. ip21systemhealthtests fails with value out of range. the recload aborts at line 1724.
|
Solution: The client can manually correct the problem and proceed immediately.
edit the file:
c:\Program Files\AspenTech\InfoPlus.21\db21\etc\ip21health.rld
In that file, line 1724 looks like this:
=05-JAN-06 15:15:00.0
Any time after Jan 5th in 2008, this value will be out of range, and will produce an error when attempting to load this .rld file. The easiestSolution is to simply remove the date, so the line looks like this:
=15:15:00.0
NOTE: there are NO spaces in the line above. Time immediately follows =.
After doing this, the date will default to the current date, and it will no longer be out of range.
Keywords: None
References: None
|
Problem Statement: For a three phase (two-liquid) system column, the temperature of a tray in the bottom half of the column, near the reboiler is lower than the temperature of the tray immedeiately above. The upper tray is two liquid phase. The tray below has a single liquid phase.
As more and more feed is added to the column, it is expected that more trays will have two liquid phases
|
Solution: Switch to local properties mode to correct the temperature inversion. Local properties is also updated at every integration step, so it is accurate and the simulation.
The rigorous properties option does rigorous k values calculations but does not include phase stability checks to ensure a phase split is always found when it should be. The checks are done in the local properties code. The rigorous formulation does not lend itself to inclusion of the stability checking.
The stability check determines if the total Gibb's free energy will be lower if the liquid splits into two phases. Using rigorous properties the single phaseSolution can satisfy all the equilibrium equations, but not satisfy the Gibb's free energy minimum. - this could result in an incorrect temperature profile
Keywords: local properties
rigorous properties
temperature inversion
temperature profile
incorrect results
two liquid phases
2 liquid phases
3 phase system
three phase system
column temperature profiel
column profile
column results
References: None
|
Problem Statement: Aspen Dynamics does not handle some component names that are legal in Aspen Plus
|
Solution: When naming a component in Aspen Plus, one must follow the naming convetion in Aspen Dyanamics inorder to export a dynamic run succesfully. Although Aspen Plus accepts component names like A-B, Aspen Dynamics does not, so a component that has a hyphen in it, must be renamed before being exported to Dynamics. (A name like A_B will work in Aspen Dynamics) If this is not done, the file will be exported, but in Aspen Dynamics the component will not show up. An example is given below:
In Aspen Plus, enter component named POLY-1, call it a Conventional component. Run the Aspen Plus file, and it converges, export the file to dynamics. In dynamics the run initializes, runs in dynamic mode, but the results do not show the component POLY-1. The results shown are:
zn(*), instead of zn(POLY-1).
Infact there is no record of POLY-1 anywhere with the Exception of the component list, where under TYPE1, POLY-1 shows up, but it says that the formula is missing.
Fixed in Release:
10.2 and later
Keywords: component name
component
name
hyphen
dash
underscore
underbar
References: None
|
Problem Statement: Aspen Watch Maker fails to run with the following error message regarding side-by-side configuration-
Run-time error ‘-2147010895 (800736b1)’: Automation error The application has failed to start because its side-by-side configuration is incorrect. Please see the application event log to use the command-line sxstrace.exe tool for more detail.
|
Solution: This issue typically occurs when VC++ 2008 Library is not installed / damaged on the machine running Aspen Watch Maker. The error message for Aspen Watch Maker in this case would typically be accompanied by an error message in the Event Viewer | Windows Logs | Application (log) that will provide a description of the problematic registry key (see screenshot below).
Activation context generation failed for C:\Program Files (x86)\Common Files\AspenTech Shared\SLM Common Error Dialog.dll. Dependent Assembly Microsoft.VC90.OpenMP,processorArchitecture =x86,publicKeyToken=1fc8b3b9a1e18e3b,type=win32,version=9.0.21022.8 could not be found. Please use sxstrace.exe for detailed diagnosis.
Installing the 32-bit Visual C++ 2008 Redistributables on the machine should fix the problem. The package can be downloaded from the Microsoft support website using the hyperlink provided above.
Keywords: Aspen Watch Maker, Automation Error, Side-by-side configuration, SLM Common Error Dialog
References: None
|
Problem Statement: I need to provide check valve in my flowsheet, I do not see in valve available that would be used as check valve
|
Solution: we do not have separate library model to use as check valve. Instead, we have conventional valve model and model it's action as check valve. To do configure as check valve, right click on any valve model and go to B1(valve) || configure and set Check valve option to be True
Keywords: Check valve,library model, flowsheet
References: None
|
Problem Statement: How do I prevent run-time error -2147220736 when starting Aspen Watch Maker?
Symptom: You see a runtime error starting Aspen Watch Maker like the following:
Run-time error '-2147220736' (80040300)': Automation error
|
Solution: The fix, in most cases, is to change the Protocol setting to Web Service instead of DCOM in the ADSA Client Configuration Tool on the Aspen Watch Server.
Additionally, if ADSA Server is not installed on the Aspen Watch server, you can do the following to allow PCWS to display the Watch Server's information:
1. Set the PCWS Web Server host name as the Directory Server in the ADSA Client Config Tool of the Watch Server (PCWS v7.3 now automatically installs an instance of ADSA Server on itself for this purpose).
2. Then, define a Public Data Source for the Aspen Watch server via the Web Server's ADSA Client Config Tool.
Keywords:
References: None
|
Problem Statement: An Aspen Process Controller application is not showing up in Aspen Watch
|
Solution: An Aspen Process Controller application is not showing up in Aspen Watch even if the ?Enable Aspen Watch Monitoring? box was checked when the application was deployed and the Aspen APC Performance Monitor Data Service and the AspenTech Production Control RTE Service are running.
In Aspen Watch Maker Actions menu \ Online Host Connection check that the Host associated to the APC controller is added. If it?s not available, add the RTE Host (it has to show the green light status, it may be required to restart the Aspen APC Performance Monitor Data Service and the AspenTech Production Control RTE Service).
The Installation Guide mentions the following:
Note: After the Aspen APC Performance Monitor Data Service is started, it waits 2 minutes before publishing any Aspen Process Controller applications to Aspen Watch Maker.
Keywords: Aspen Process Controller, Aspen Watch Maker, RTE, Online Host
References: None
|
Problem Statement: How do I model column overhead system rigorously in Aspen Plus Dynamics?
|
Solution: While configuring the steady state model in Aspen Plus, you are allowed to model condenser in instantaneous model. You are only allowed to configure heat transfer rigorously in dynamic. Now, you would be able automatically reconfigure a Radfrac column with a condenser into an external condenser in Aspen Plus Dynamics. To use this feature select “External_Condenser� from the column scripts menu. This results in a fully specified multi-block Radfrac model with an external condenser. No additional initialization efforts are required. Key benefits of an external condenser:
· Allows detailed modeling of the overhead system without having to configure it in Aspen Plus (which may be difficult to converge). Use only the Radfrac block in Aspen Plus and then use this new feature to expand the overhead system. You can then add pumps, heat exchangers, etc. to expand the overhead system
 Adding instantaneous models in standalone dynamics is straightforward if you set flashbasis to procedure.
Â
Keywords: condenser, overhead
References: None
|
Problem Statement: How to configure dead band controller in Aspen Plus Dynamics?
|
Solution: One can specify the lower (DBlow) and upper (DBhi) limits to specify the lower and upper limits of dead band as a percentage of the process variable range (PVmax?PVmin) by going to controller configure button ( Face plate || Configure || Other).
If you wish to specify a dead band either side of the controller set point and if the process variable is within this dead band, the controller output is not changed.
Let's consider the level of a water tank is monitored.
The set-point is set to comfortable operating water level of 5m. The dead band is set to a minimum water level of 1m. With these settings the outlet valve controlled by the alarm allows water to exist the tank only open if the water level rises above 5m, and will close if the water level falls below 1m.
Keywords: Dead band, Face Plate
References: None
|
Problem Statement: A RADFRAC block is converged to steady state (with the steady state run mode), then the simulation is left running without external disturbances. After a while, one sees the compositions, temperatures, flowrates, etc changing dramatically. Why?
|
Solution: The reason may simply be that the steady state is unstable. When looking at dynamic simulation, one has to remember the importance of the control system. Aspen Dynamics adds automatically level and pressure controllers, because without these, drums would run dry or full after accumulating any small deviation from the balance of the flow in and out. However, this does not guarantee that the simulation is stable, as for example there is nothing to control the energy contents, or composition control, etc.
The steady state simulation eventually deviates without external disturbance because the numerical integration can introduce some noise in the reSolution, hence there is always some sort of disturbance present. You can reduce this noise by thigthening the tolerance, but because the intrinsic problem is still present, you will only defer the effect.
One way to study the stability of a system is to look at the eigenvalues of the state-space decomposition matrix A. If any eigenvalue has a real part that is positive, then the system is unstable. You can evaluate the state-space decomposition with CDI. The matrix can then be analyzed with tools such as Matlab, or some programming to call a routine to evaluate the eigenvalues.
See the attached examples. The first column is methanol-water. The analysis shows that the column is stable with the default control system. If you run the simulation in dynamic run mode, you should see that the simulation remains stable.
To run the example:
open the dynf file (which is a flow-driven export of the bkp)
change the run mode to initialization
run
change the Global, PropMode to Rigorous
run
change the run mdoe to Steady State
run (a kept result steady-state has been created at this point)
invoke the script to generate the A matrix (flowsheet, script cdi_script)
to analyze the matrix, the fortran program (using IMSL fortran library) can be used
This reports no eigenvalue has a positive real part.
The second example is benzene-methanol (this forms a low boiling azeotrope). The analysis shows that the column is unstable. If you run the simulation in dynamic mode, you will observe that after a while the column goes to a new steady state. If you step the reboiler duty by a small amount, you will observe that the column goes to a new steady state which is very different after about 20 hr. (The simulation is then in troubles, because vessels are overfilled, etc).
To run the example, you can repeat the same steps as for the first example. This will report that one eigenvalue has a positive real part.
Note that if you control the level in the reboiler drum by manipulating the reboiler duty, then the second column is stable.
Important remark: in order to evaluate correct state-space matrices, you have to use Rigorous properties and turn off tearing.
Keywords:
References: None
|
Problem Statement: A controller is loaded into AspenWatch using AspenWatch Maker, but when the collection should have stabilized, the Run Status doesn't show Success. It shows Validation Error.
|
Solution: is applicable to all versions of AspenWatch
Keywords: AspenWatch, Context Server, Maker, cimio
References: None
|
Problem Statement: How are the stage efficiencies defined in Aspen Plus Dynamics (APD) for distillation columns?
|
Solution: The efficiencies in APD are defined in the same way as in Aspen Plus. The screen shot below from the A+ Help shows the definition of the efficiencies. In APD, the efficiency values are in the property submodels used by each stage, for example, B1.stage(1).pflash2(1).eff(?ethanol?). The same variable is used for vaporization and Murphree efficiencies. The parameter EffType (e.g. B1.stage(1).efftype) controls whether this is interpreted as a Murphree or vaporization of stage efficiency.
Another variable named effo (e.g. B1.stage(1).effo) is a correction term used in the hydraulics equations in the stage model. It is the same as the overall section efficiency defined in Aspen Plus, shown on the next screen shot:
This can be used to reflect that an ideal stage is equivalent to more than 1 real stage, and so has greater liquid holdup. The holdup on an ideal stage is calculated from ?ideal stage holdup? = ?real stage holdup?/?section efficiency for stage?.
Keywords: efficiency, stage
References: None
|
Problem Statement: Is it possible to change the values of fixed variables while a dynamic simulation is running? If yes, then what are the options?
|
Solution: Yes, it is possible to make changes in fixed variable input while the dynamic simulation is running.
This can be performed in two different ways:
1. Make changes in the Manipulate Table of any feed streams and/or unit operations.
2. Make changes in the Controller FacePlate Form setting.
Please follow the steps:
1. From Manipulate Table
Right click on any Feed stream or Unit and open “Manipulate” Table.
Please enter new value for any Fixed variable and press “Enter”
For an example, we can change the molar Feed flow rate which is a Fixed variable.
2. From Controller FacePlate
Please double click on any Controller to open the FacePlate Table and make changes.
For an example, we can change the Set Point (SP) value.
In both cases of Manipulate Table and FacePlate, always press “Enter” or click somewhere in flowsheet, otherwise the change made will not take place.
Key Words
Dynamic Simulation, Fixed Variables, Manipulate Table, FacePlate
Keywords: None
References: None
|
Problem Statement: The following translation error occurs when a simulation containing pseudocomponents generated from assays or blends is exported:
TRANSLATE USING COMPILED AST PROCEDURES IN D:\Program Files\AspenTech\Aspen Dynamics 11.1\Ast DIRECTORY.
TRANSLATING FEED STREAM FEED of TYPE MATERIAL.
363: ERROR: Variable ADA is undefined
363: One or more items of result data are missing. Please re-run the simulation and try again. 363: FATAL ERROR: Aborting procedure D:\Program Files\AspenTech\Aspen Dynamics 11.1\Ast\FEEDM.TBL
|
Solution: The simulaton is missing some property parameters which need to be included in the *.appdf file which is exported.
To include them, click the checkbox named Pseudocomponent property parameters (in SI units) on the Setup Report Options ADA Sheet. Save and re-run the simulation in Aspen Plus and export to Aspen Dynamics.
Keywords: pseudocomponents
pseudo-components
assay
blend
file
export
References: None
|
Problem Statement: Upgrading custom calc from 2004 to version 2006.5, what are the differences?
|
Solution: See attached document New versus Old KPI Calcs.
Keywords: KPI, calcs,
References: None
|
Problem Statement: How can I user specify a bias in PID controller?
|
Solution: There are two versions of PID in Aspen Plus Dynamics, 1) Simulation | Libraries | Dynamics | SupersededModels | PID, and 2) Simulation | Libraries | Dynamics | ControlModels | PIDIncr. This first one is based on a positional algorithm, while PIDIncr uses a incremental algorithm. On the Configure dialog of PID, there is a field for bias. PIDIncr is recommended.
If you specify an initial value for the variable OPMan to initialize a PIDIncr controller model output, this has a similar effect to using a bias term.
For more details, refer to the online Help.
Keywords: Bias, PID controller
References: None
|
Problem Statement: When generating KPI averages, I get different results depending on the method used to request the data.
|
Solution: From the KPI Plot page of the PCWS - History
1. Select Monthly.
2. Then select either From current time or Time ending at (use today). (Refresh the page after each time selection)
Method one, Select Monthly provided one value and Method two generated a different value.
It has been determine that method two was actually requesting the monthly average from the previous month.
This was corrected for version 2006 by updating a series of SQL files.
Download the SQL zip file attached to thisSolution and update the Ip21 database by doing the following:
In the AspenWatch server machine,
1. Extract the three SQL files from the attached zip file and store in the temporary folder.
2. Open Aspen SQLplus (using Start->Programs->AspenTech->Aspen Manufacturing Suite->Aspen SQLplus).
3. Using File->Open in Aspen SQLplus to open the three SQL files one by one.
4. Save each of the sql to IP21 database by using Record->Save As... and remove .sql in the Record Name filed of the Save Record dialog window.
Keywords: None
References: None
|
Problem Statement: Is it possible to use non-reverse flow models with reverse flow models in the same simulation?
|
Solution: It is possible to use non-reverse flow models with reverse flow models. The steps are:
1. Isolate the non-reverse flow models with valves
2. Set the check valve option to true.
However the best practice is to avoid using reverse flow and non-reverse models in the same simulation to improveSolution speed and convergence.
Key Words
Reverse Flow, Non-reverse Flow, Valve, Convergence
Keywords: None
References: None
|
Problem Statement: 1. Steady state analysis where all CV ssa's are of the form:
CVname causes a x.xx change for NONE
2. constraint reporting inaccuracies.
3. Missing or invalid values handled incorrectly in reports
4. Try to generate report from PCWS and get following error message if no controller in ID 1
Error description:[AspenTech][SQLplus]InfoPlus.21 record C01_AGG does not exist
5. Under some circumstances, the management report would not gather data for all controllers.
6. There were problems when the DELTATIMESTRING hours were greater than 99.
7. There were a number of other small multi-controller problems that were fixed.
8. Dependencies on whether or not the CLP was present were removed, and there is better information about data collection
9. Some of the modifications were done in AW_RPT_HISVALUE(), and AWP_CheckAPPHisData.sq. so they must be applied as well to get proper results.
|
Solution: Download the attached zip file.
Create a subdirectory under ...\AspenWatch\ called patches
e.g. c:\Program Files\Aspentech\AspenWatch\patches
and unzip the contents of this zip file into that directory.
Run the batch file.
The batch file will save a snapshot of the current state of your database (before applying these patches) into your current default directory (presumably ...\AspenWatch\Patches), and will then replace the procedures to fix the behaviors described above.
If there are problems, you can revert to this saved snapshot to restore original behavior.
Keywords: Steady State Analysis
SSA
Management Reports
References: None
|
Problem Statement: An effective control structure in a distillation column requires a thorough investigative analysis of column behavior from steady state calculations. Several different methods are discussed here while working on building the control structure of a distillation column. Please note that this study is performed in a steady state run and can easily be implemented in Aspen Plus by design Spec/ sensitivity analysis prior to export in dynamic world.
|
Solution: The objective of dynamic control of an ideal distillation column is to maintain purity in the overhead and bottom usually based on two key components ( light key and heavy key). Control structure generally implemented to measure the composition of two product streams and manipulate two input variables.
However, very few columns use such compositions based controllers as they're expensive and not reliable. Instead, temperature controllers are used widely as inferential control of compositions. Unlike composition counterparts, these control provide fairly accurate control of composition if they are implemented in accurate locations. Moreover, temperature sensors are reliable and have very small dead time in the measurements.
While selecting tray temperature, one needs to thoroughly investigate column thermal and hydraulic behavior particularly in steady state run. There are several methods which are used prior to implement column control:
1) Slope Criterion: According to this method, the column temperature profile is investigated, looking for largest change in temperature. Large change in controllers indicate where the composition of key components is changing significantly.
2) Sensitivity Criterion: Similarly to slope criterion, the column response is investigated with a small change of manipulated variables like reflux flow rate, reboiler duty respectively. The largest changes in temperatures are indicative area of column control.
3) Invariant Temperature Criterion: Feed composition are allowed, keeping distillate and bottoms purities held constant. Tray is selected to control where temperature does not change with feed compositions. This method is difficult to implement particularly in multicomponent systems.
4) Minimum Product Variability Criterion: According to this method, the tray is selected where there is smallest changes in product purity observed when temperature is held constant in presence of feed composition disturbances.
Keywords: Sensitivity, Slope, Column Dynamics
References: : Distillation Design and Control Using Aspen Simulations, By W. L. Luyben, John Wiley & Sons, Inc
|
Problem Statement: Unable to retrieve aggregate information for miscellaneous tags
|
Solution: This should provide aSolution for retrieving aggregate information for miscellaneous tags from Aspen Watch 2006.
Attached are two SQL files that are needed to update your system, upload them from Aspen SQLplus.
The statement to use for retrieving the aggregated hourly information will be like this:
AWHistory('MISC','03FI1668PV',,'17-JAN-2010 00:00:00','-01:00:00','AVG',24);
Keywords:
References: None
|
Problem Statement: Inconsistent results when reading PID loop parameter from different servers
|
Solution: You are reporting that the test api results are different for the two different machines.
The first thing is to confirm the value being used for the listid. A listid of -1 says go to the device and get the data, a listid of 1 says read from the context. Depending on where you run the T-api from, sometimes it seems the default may be set to 1 and sometimes to -1.
When using the T-Api utility, always use a listid of -1 to confirm connection and retrieval from the device.
Keywords: cimio, t-api, read, values, different
References: None
|
Problem Statement: In the attached simulation, if the pressure of the product stream is ramped up, the simulation fails to converge. Why? What can be done to prevent this to happen?
|
Solution: A pressure driven simulation must have the correct topology, i.e. blocks with a vapor holdup cannot be connected directly, and there must be a pressure driven element, such as a valve, between them. The pressure checker tool can be used in Aspen Plus to detect these constraints.
However, even when the topology is correct, the simulation may still fail to converge. In thisSolution we expose one of the cause that can explain this convergence failure.
In the attached example pres-fail.bkp and pres-fail.dynf, the product pressure in stream 11 is ramped up to 8 bar. Once the stream 7, the vapor flowrate leaving the second flash block F-2, becomes zero, we observe that the simulation fails to converge. If reverse flow was enabled, reverse flow should follow, i.e. some vapor would flow back from the mixer M-1 into the F-2. As the reverse flow is not enabled, the pressure in F-2 cannot track the pressure in M-1, hence there is noSolution to the equations and the simulation fails to converge.
To run the simulation, open the file pres-fail.dynf, use the kept result start, open the TPFmPlot for stream 7, run the dynamic simulation and observe that it fails at time around 0.49 hr.
The work around is to add a valve on stream 7, the vapor outlet of F-2, even if the pressure checker does not strictly require it. This valve, even with a small pressure drop, will act as a check valve. So when the flow in stream 7 is zero, the downstream pressure will be allowed to become greater than the pressure in F-2, and the simulation will run. The valve has been added in Aspen Plus, the simulation has been exported as pressure driven and controller PC4 which manipulates the valve position V-5 has been removed.
To run the simulation, open the file pres.dynf, use the kept results start, open the TPFmPlot for stream 7, run the dynamic simulation and observe that it runs smoothly.
As a conclusion; if you observe that a simulation is failing to converge when the flow becomes zero in a pressure driven simulation, consider adding a valve with a small pressure drop as it may resolve the problem.
This is a limitation of the pressure checker. We will investigate how to resolve this issue in a future version.
Keywords:
References: None
|
Problem Statement: Sometimes the DMCwatch task (tsk_cl01 through tsk_cl05) will abort and cannot be re-started, or will fail immediately after re-start. There may not be helpful information in the .out or .err file.
|
Solution: When there is not helpful information, the tasks can be caused to generate more trace information so that the user (or support personnel) can determine what the process was doing when it terminated. With this information, it is easier to find what needs to be changed for the task to continue to run.
It is also possible that the AWcollect task (tsk_aw01 through tsk_aw05) could abort, though much less likely. If it does, the same technique can be used for that as well.
Please do not use these techniques without reading and understanding the caution at the end!!!
For any of the 10 tasks, you can put the character string debug diag (no quotes, of course) in the command line parameters, then stop and re-start the tasks to start them running with the new parameters.
For the purposes of this tip, the sole value of the output, is that you can see what the task was doing when it stopped, so go immediately to the bottom of the file (it will frequently be quite large) and try to work backwards to see what it was doing. Usually, the problem is one of the cycle-to-cycle files, or loading the model file or something like that. If the problem is evident when you go to the bottom of the file to see what it was doing, then make the correction: delete the .ctc file and allow tsk_cl0x to re-create it, or clear up whatever problem is preventing the task from reading the model file. If the file makes no sense to you, you will have it to e-mail when you call support.
AWcollect is usually less fragile than DMCwatch, so there has not been a pattern emerge that can be provided as clues to what the problem might be. If AWcollect is the task that is failing, zip the output file and have it ready to e-mail to support, then call support.
CAUTION!!! This will generate a LOT of output in a very short time. The debug diag parameters are suitable ONLY when you know the task is going to abort very shortly after startup. After you have finished generating the file, and corrected the problem, REMOVE the debug diag parameter, stop and re-start the task. You might even check the .out and .err file to make sure it is not growing without bound. If you leave it generating output, it could fill up your system disk and cause your computer to crash. As long as you keep this in mind and are careful, it should be more useful than dangerous.
Gratis information: The two most frequent problems with AspenWatch are:
The configuration files (.ccf and .mdl) have changed in the DMCplus installation, but the new files have not been migrated to the AspenWatch computer, and been updated using AWmaker.
There has been a service pack or an Engineering release applied, and the user has failed to run Install Database Configuration
Keywords:
References: None
|
Problem Statement: Inspector fails to start. Generates a pop-up dialog box saying: Unable to start IP21 API Manager
|
Solution: Insure that Process Data for IP.21 has been installed.
During installation in the Select products dialog, check the box labeled Aspen Process Data, then click the button labeled Select Subcomponents. In the Select Subcomponents dialog check Process Data for InfoPlus.21 and Setcim.
this should resolve the problem for Inspector, but if you are running some other products, it might be a good idea to also check Process Data for Web.21 (for plotting in the PCWS) and Process Data for AspenCalc for calculations done in IQ and DMCplus Simulate.
Keywords: AspenWatch
References: None
|
Problem Statement: The AllVariables table is not showing all the variables. How can I fix that?
|
Solution: Some variables have been declared in the models or stream types with the HIDDEN keyword, such as:
PVsf as hidden percentu (rateinitial, 50); // Scaled & filtered input signal
(this is a line from the PID controller model in Dynamics library) This causes the variables to be not displayed on the various forms, such as AllVariables, Results, etc. You can display these variables if you wish:
Tools, Settings, Preferences
tick the option Show Hidden Variables
This setting is saved in the user registry, not in the dynf/acmf file. So you need to repeat this operation on any computer you require to display the hidden variables. The setting is common to Aspen Dynamics and Aspen Custom Modeler (and other derived products).
In version 11.1 and above, you can also modify standard forms, to display or remove variables. To revert to the original definition, do a right mouse click on the table and select Reset Form properties.
By convention, hidden variables have no description. You need to edit the model, where usually we have added as comment a short description of the variable.
When would you need to look at hidden variables? Most of the time, you would actually not need to worry about them. But as in the example of PVsf, note that this variable is specified as a rateinitial. It may be important to know its starting value, or be able to change the specifications (for example to make it initial instead of rateinitial, or give a different initial condition, etc).
Finally, note that forms display only active variables, i.e. variables that are effectively used by some equations. So, if the variable is not hidden, and does not display after restoring the form properties, it's highly likely that it is not active.
Keywords:
References: None
|
Problem Statement: In some instances, the export function to extract AspenWatch data on the Production Control Web Server (PCWS) would get stuck and the following message appears when the user tried to extract more data.
|
Solution: The export function may get stuck when the TSK_IQx that used to extract the data is hung up.
To reset the error, locate the AW_TagExporter record in InfoPlus.21 Administrator.
Change the status from Busy to Idle (and press Enter).
Next shutdown IP.21 with InfoPlus.21 Manager. After IP.21 is down, look in the server's task manager and kill any orphaned IQtask.exe left running. Start up IP.21 back up and the system should be ready to extract more data.
Keywords: AWTagExport
APC Web Interface
PCWS
Aspen Watch History
References: None
|
Problem Statement: How to model compressor inertia in a combined turbine compressor system, or multiple compressors on the same shaft?
|
Solution: The difficulty is that while the compressors should be modelled with separate blocks, their mechanical inertias cannot be modelled separately, otherwise this would lead to an index>1 problem which can not be handled by the integration methods available in Aspen Dynamics.
You need to lump the mechanical inertia of all machines which are on the same shaft, use the Instantaneous option for all but one block.
The compressor using the Dynamic option should be assigned the mechanical inertia of all machines (and possibly gear box, electrical drive, etc)
You need to correct the inertia of the other compressor by the square of the gear box ratio. That is to say if the other compressor is spinning faster, its inertia counts more.
Keywords:
References: None
|
Problem Statement: Standard KPI hourly averages associated with Miscellaneous (MSC) tags configured without an IO source show -9999.
|
Solution: Miscellaneous tags in AspenWatch can be build without IO by running an SQLplus script that uses the procedure AWP_ADD_MISCTAG similar to the statement below.
--
PROCEDURE AWP_ADD_MISCTAG(TAGNAM CHAR(24), MSCDESC CHAR(64), ENGUNT CHAR(32),
PLOTH REAL, PLOTL REAL, TSKID INTEGER, DEVICE CHAR(24), IOUNIT INTEGER,
FREQUENCY INTEGER, IOADDR CHAR(80), POINTTYPE INTEGER, IORECTYPE INTEGER,
PVHILIM REAL, PVLOLIM REAL, PVDELTAHI REAL, PVDELTALO REAL)
When defining MSC tags using this procedure, the AspenWatch is unable to process the aggregate KPI calculates for the tags due to missing information. The values of aggregate KPIs are therefore displayed as BAD data (-9999).
In order for the tag KPIs to be processed properly, the user would have to enter a non-zero, positive frequency (AW_SCANRATE parameter) for each of the MSC tags added using the above procedure.
Keywords: Aspen Watch
Miscellaneous KPI
References: None
|
Problem Statement: When you run a simulation after creating a DMCplus controller in Aspen Dynamics flowsheet, you get an error message like:
DMCplus Interface: Error when attempting to start controller MCHCOL
Please check that the ACO Utility service is started.
Also check that you have correctly configured your License Management.
|
Solution: As advised in the error message you need to check that the products are correctly installed:
DMCplus Online 2.1 and its required components
See the installation manual of DMCplus Online 2.1 for instructions. The typical problem is that you need to use the DMCplus controller with the same login as the installation, and you need Log on as a service authorization rights (see installation manual for details).
You need the license to use both DMCplus Online 2.1 and Aspen Dynamics.
You need to check that the ACO Utility service is started. Go to Start/Settings/Control Panels, then select Services. You should have ACO Utility Server with the status Started and Startup as Automatic. You can check with the NT Administration tools, Event Viewer.
Note that if you change your password you may need to update the settings of the CIM-IO server, under Control Panels, Services.
Another potential cause for the problem is if the controller files are not copied in the DMCplus installation directory. You need to copy the controller configuration file (.ccf) and the model file (.mdl). The name of the controller is selected in Aspen Dynamics via the string parameter ControllerName in the DMCplus block. For example if your controller block parameter ControllerName in Aspen Dynamics is assigned to MCHCOL, you need to copy the files MCHCOL.ccf and MCHCOL.mdl into the DMCplus directory. (It is not case sensitive)
(By default, this directory is C:\Program Files\AspenTech\AC Online\app. You then need to create a directory with the block name, in this example MCHCOL)
Keywords: DMCplus
References: None
|
Problem Statement: How do use files created in Aspen Dynamics version 10.x in version 11.1?
|
Solution: You must recreate the appdf file using Aspen Plus 11.1 else you will get this error:
Error: Unable to load file filename.appdf
Error: Could not initialise Physical Properties system.
Warning: Invalid estimation solver, reset to default.
SAICOF-F-Error in copying PDF File
>>x:\path\filename.appdf
Physical Properties have not been initialised.
Move/Save the 10.x dynf file to a new directory
Load the Aspen Plus backup (bkp) file in Aspen Plus 11.1 and run the simulation
File\Export the 11.1 dynamics file; this generates the dynf and appdf files
Copy the original 10.x dynf file back into this directory.
The 10.x dynf should now load ok in Aspen Dynamics 11.1
Keywords: dynamics
version
10.1
10.2
appdf
dynf
upward
compatibility
References: None
|
Problem Statement: The flow rates in Aspen Dynamics RGIBBS model do not match Aspen Plus results and are out of mass balance (in flow <> out flow). This happens when the flow rates are very small, such as fuel cell (type) applications.
|
Solution: The work around is the scale the flow rates using the MULT block before and after the RGIBBS model, i.e. have a MULT block before the RGIBBS block to scale up the flow and then have a MULT block to scale down the flow rates.
Scheduled to be fixed for Aspen Dynamics 11.1 SP1.
Keywords: RGIBBS, mass balance
References: None
|
Problem Statement: In earlier versions of Aspen Watch, there was an option to Generate CCF from the Inspector. Has this been removed from 2006.5 onwards? If this is removed then how do we simulate process for the past history?
|
Solution: It is possible to Generate CCF from Inspector from the PCWS after the following updates have been applied:
Install CP1, followed by the latest Hot fix for 2006.5. The instructions are documented in the list of corrected issues in the hot fix.
CP1 found inSolution 123288
HotFix2 - Aspen Watch 2006.5Solution 125179
Hotfix2 - PCWS 2006.5Solution 125459
Keywords: web server, inspector, aspenwatch, pcws
References: None
|
Problem Statement: Windows NT crashing on Aspen Watch server computer, resulting in a blue screen.
|
Solution: [Mr. Jeff Lawrence from ExxonMobile EMRE submitted the following tips to prevent Aspen Watch system crashes.]
The system crashed when I was not watching and archiving the Aspen Watch reports because the system disk completely filled. To get around this, I implemented a monthly maintenance routine that includes archiving off report files and also backing-up the IP21 database on the data disk. Since I started doing this, we have not experienced any crashes due to the system disk filling-up. [Aspen Watch version 1.2.0 provides a facility to automatically archive report files into monthly zip files. Document ID #103057 in the Technical Library Knowledge Base on the AspenTech Technical Support Center web site contains a number of files to help with backing up Aspen Watch. (The knowledge base can be accessed by going to http://support.aspentech.com, logging on, selecting Manufacturing Suite - Advanced Control and clicking Knowledge Base on the sidebar frame.)]
[Mr. Lawrence was experiencing occasional blue screen system crashes (unrelated to Aspen Watch reports) until he took the following actions.] I discovered that the Aspen Watch computer's main system drive was formatted as FAT32, which is the default format when NT is installed. I converted to NTFS format to take full advantage of the NT file handling and properties system. This also allowed me to use Norton's Speed Disk for NT and very efficiently defragement the live system drive. Using the NTFS format allows Speed Disk to defragement the directories, system PageFile, system MFT files, etc. To the best of my knowledge, SpeedDisk is the only product available that can do a complete defragement (including system files) while the system is up and running. Defraging also increases the speed of the system by reducing file access time from the hard disk. I have also used Speed Disk on the IP21 data disk. [InfoPlus.21 was shutdown while defragmenting.]
I also fixed the pagefile size to a large value in the NT configuration and specified that it not be dynamically sized. Part of the reason we were able to crash the system with the reports filling the disk is that the reports probably consumed the dynamic pagefile area. This meant that when the system needed more pagefile area and couldn't find it, it started crashing.
Keywords: AppTool
References: None
|
Problem Statement: Aspen Process Explorer, version 2.5.1 (which is part of Aspen Watch 1.2) installs a system service which causes a conflict with a service installed as part of the Aspen MIMI installation. If both Aspen Process Explorer, version 2.5.1, and Aspen MIMI are installed on the same computer, you can remove this conflict by performing the following actions:
|
Solution: Open the Control Panel (Start -> Settings -> Control Panel) and double-click the Services icon.
Scroll down to the service named NobleNet Portmapper, select it, and click the Stop button.
With NobleNet Portmapper still selected in the list of services, click the Startup... button. The Service dialog window appears.
Under Startup Type, select Disabled and then click OK.
Scroll back up to the service named Chesapeake Distributed MIMI Request Broker. Start this service by selecting it in the list and clicking Start.
Keywords: Process Explorer, MIMI, NobleNet Portmapper
References: None
|
Problem Statement: Existing PIPE (PIPE3/PIPE2) models in APD are not robust in shut-down condition, especially for a flow reversal with bi-directional flow build up within a pipe. Current discretization method and the boundary condition models are not good enough to get through such difficult moment.
|
Solution: There could be workaround on this issue. The workaround may or may not work depending on the problem type. Main problem is that the current pipe model cannot handle a bi-directional flow, such as <-- --> or --> <-- flow condition. Imaginable workaround is making flowsheet or model not to create such bi-directional flow condition. Otherwise using multiple pipe models instead of single pipe. And then for each of multiple pipe should be configured not to make a bidirectional condition. For the pipe model, if you set the interior node number as 2, then it will be no longer a pipe but just a void. However it is more functional than a void, since it calculates more information, such as pressure drops. If you connect multiple void-like pipe models in series. Then it will be like an integrated pipe-segment model.One clear advantage from such pipe-segment model is that it won't cause a bi-directional condition therefore it will be robust in most of flow conditions. However a drawback would be it would be less-accurate than a real discretized pipe model.
Keywords: discretization, bidirrectional, pipe-segment
References: None
|
Problem Statement: Cannot assign a units of measurement in a ramp like you can with an assignment in a task?
|
Solution: The fix for using the {units} syntax in a ramp has been deferred to a future unspecified release.
However there is a work-around as follows, for using a temperature in Fahrenheit instead of Celcius (the library unit of measurement for temperature):
Task test_ramp runs at 0.1
finalu as realparameter; // to store the converted value
invoke (finalu) : convert_value (B1.T1, 30, F); // name of the variable to ramp as a string, value, units
ramp(B1.T1, finalu, 0.2); // the ramp
End
Keywords:
References: None
|
Problem Statement: Change a controller from one AWCollect/DMCwatch set to another
|
Solution: Sometimes the user either selects an inconvenient pair of tasks for tsk_AW01-5/tsk_CL01-5, or changes in the operating parameters of the controllers make it desirable to change the tasks to which certain controllers are assigned. This cannot be done using update in AW Maker. Here is a procedure to make this change:
[NOTE] that the external task records are paired. I. e. tsk_aw01 is paired with tsk_cl01; tsk_aw02 is paired with tsk_cl02, etc. be sure to maintain this paring in the following procedure.
This explanation assumes that the user is reasonably familiar with IP.21 Administrator, Record fixed areas, and Record repeat areas.
To change a controller so it is using a different set of tasks (tsk_aw0x and tsk_cl0x), only two changes need be made, but the records where they are changed must be made unusable, and to do that, references must be removed and then restored. use the following procedure:
First - using AW Maker stop the collection on the controller where the change is to be made.
The two records that must have changes to the EXTERNAL_TASK_RECORD field are:
The controller record, which is defined by AW_CTLDef, and is named: <controllername>_<logical device name>
for example:
col5x3_iodmcp. (This name will be used in explanation.)
The Calculation record, which is defined by AW_CALDef and is named C0x_ACT, where the x is the id of the controller. This can be seen in AspenWatch Maker, or in the field AW_CTL_ID in the controller record defined above.
To change the EXTERNAL_TASK_RECORD field in the controller record:
Set the AW_ARCHIVING_x (x=1,2,3) switch to off for the record being changed.
Right click on the record in the left hand pane of IP.21 Administrator and select make unusable. A dialog box will pop up labeled
Keywords: None
References: s to col5x3_iodmcp and will show two references:
AW_CTL_LIST <x> AW_Children <x> is an occurrence number; AW_CTL_LIST is a record defined by AW_FOLDERDef
C0n_AW_Monitor <y> WAIT_FOR_COS_FIELD <n> should be the same controller ID as for the name of the calculation record; <y> is an occurrence number - usually 1; C0n_AW_Monitor is a record defined by QueryDef
Make sure you can find these references so you can restore them after you make the record usable again.
After you verify you can find and restore these references, click on the button labeled Remove All and Make Unusable.
Change the field EXTERNAL_TASK_RECORD to the desired AWCollect task, e. g. tsk_aw05.
Right click on the record name again and select Make Usable
Restore the references removed in step 2 and 3.
Set Archiving back to on (reverse step 1.)
To change the EXTERNAL_TASK_RECORD field in the calculation record:
Right click on the record name for the appropriate calculation record in the right pane of IP.21 Administrator, and select Make Unusable. A dialog box will pop up labeled: References to C0x_act and will show a reference:
C0n_ACT_SCHE <x> RECORD_NAME.
(<n> is controller ID; <x> is an occurrence number, usually 1 C0n_ACT_SCHE is a record defined by ScheduledActDef).
After determining you can restore the reference as in above step, click the button labeled Remove All and Make Unusable.
Change the field EXTERNAL_TASK_RECORD to the desired DMCwatch task, e. g. tsk_cl05.
Right click on the record name again and select Make Usable
Restore the entry in C0n_ACT_SCHE <x> RECORD_NAME.
After completing the changes - using AW Maker, start the collection for the changed controller.
AspenWatch should start collecting on the new tasks immediately. If it does not perform the following remedial action in order of least drastic to most drastic.
stop and start the new tasks (tsk_aw0n, tsk_cl0n) using IP.21 Manager.
stop and start InfoPlus.21.
reboot the computer.
call AspenTech Support.
|
Problem Statement: I'm modelling the depressurization of a storage tank with ethylene at high pressure, using a Mixer block. When I close the feed valve and leave the outlet valve opened, the temperature in the mixer drops to very low value. Is that correct?
|
Solution: The dynamic simulation uses rigorous material and energy balance. The temperature change is caused by the pressure drop in the storage tank.
The material balance can be written as:
$M = -F
where $M is the derivative of the molar holdup (e.g. dM/dt), and F is the outlet flowrate ($ stands for the time derivative in Modeler language, which is used in Aspen Dynamics).
The energy balance is:
$E = -F * h
E is the internal energy (we ignore gravity, electrical and magnetic energies). The thermodynamic principle says that it is the energy that matters in the energy balance. However, for the inlet and outlet streams, we need to use the enthalpy, as the flow of material requires a compression work (for the fluid to enter the vessel) or expansion (for the fluid to leave the vessel). This is well explained in many good books on thermodynamic, see for example Smith and Van Ness introduction to chemical engineering thermodynamics, page 213. This energy balance assumes that the tank is adiabatic.
The enthalpy h is calculated from the internal energy u, plus the compression, e.g. h = u + p*v, where p is the pressure and v the molar volume. As we use Aspen Properties, we actually get the enthalpy, and the internal energy can be calculated from u = h - p*v.
So, the total internal energy holdup E is:
E = M * u = M * (h - p*v) = M * h - p * V
where V is the total volume of the vessel (because M v = V as the material fully occupies the vessel volume).
If you look at the Mixer model, you will find around line 390 the actual implementation of this energy balance:
// internal energy constraint from H = U + pV (where V is total volume occupied by
phases)
IF (EqHeatCap == No) OR ((EqHeatCap == Yes) AND (EnvHtTrans == Yes)) THEN
IF (ValidPhases == Liquid-Only) THEN
E = M*h - UCF13*P*Vl;
ELSE
E = M*h - UCF13*P*V; // line 390
ENDIF
The conversion factor UCF13 to convert from bar m3 to GJ. The value is 1e-4, because 1 bar = 1e5 Pa, 1 Pa x 1 m3 = 1 J, and 1 GJ = 1e9 J, so the factor is 1e5/1e9 = 1e-4. This conversion factor is due to units used in Aspen Dynamics, E is in GJ, h in GJ/kmol, M in kmol, p in bar and V in m3.
Note also that this drop of temperature happens even for ideal gas.
This drop of temperature may look unrealistic, but this is rigorous and correct. One can experiment this for example when dismantling a nearly empty gas cylinder of a camping burner: as the remainder of the gas escapes to atmosphere, one can feel the cylinder getting very cold. In reality, you would have to account for the metal mass of the tank, and possibly some heat loss (e.g. gain) to the environment.
As a side comment, many papers in literature use the expression E = M h, e.g. they ignore the PV term. This is incorrect, but it is useful to see what happens if this term is ignored in Aspen Dynamics, by customizing the model (you need a custom modeling license for that). The temperature does not change when this PV term is not accounted for.
A bkp file is attached to illustrate with an example, a storage tank of 8.4m3 contains C2H4 at 20 bar, 25 C. Just run and export the simulation as pressure driven to Aspen Dynamics. At time zero, the feed valve position is set to 0% (in Manipulate table of valve V-FEED). The plot below shows the temperature, pressure and flowrate of the outlet stream. The temperature drops to around -150 C. The flow eventually stops as the pressure in the tank is equal to the outlet stream (1 bar), since this is a pressure driven simulation.
To see the effect of the thermal inertia, you can change the dynamic options in Aspen Plus for the mixer block, re-run and re-export the simulation, or do the change directly in Aspen Dynamics. Restart the simulation, change in the Configure form of the Mixer block the parameter EqHeatCap to Yes, and enter the mass of the vessel (e.g. 1000 kg). The EquipCp default value is ok for steel. Note however that you must change the initial specification, as the default is E as initial, but since the mass of metal needs to be accounted for (E = M*h - P V + cpmetal Mmetal * T) we would have to compute the new value of E, or more simply, change in the AllVariables table, the spec for E to Free, and the spec for T to Initial, so that the initial condition is now set on the temperature (25 C).
The plot shows the same scenario, e.g. feed valve closed. You can see that the temperature drop is much smaller.
Finally, let's study the effect of the heat transfer: the previous case assumes that the temperature of the metal is the same as the temperature of the gas, e.g. the heat transfer is infinite. In practice, it is much smaller, possibly around 0.01 kW/m2/K. To model this, change in the Configure table the parameter EnvHtTrans to Yes, set Uenv to 0 (no heat loss to environment) and UWall to 0.01 kW/m2/K. The plot shows the new results. You can see now a transient of the temperature to -35C (due to gas expansion) and a recovery to roughly the same temperature as in the previous case.
This plot shows the temperature of gas and the temperature of the metal (Twall).
Finally, this plot shows the results with the customized mixer model when the parameter UCF13 is set to zero, e.g. the PV term is ignored.
Keywords: None
References: None
|
Problem Statement: How to implement Anti Reset Wind up in PID controller
|
Solution: In current PIDincr controller, it implements anti reset windup by default in common with modern industrial controller. We are limiting the OP when clipping occurs. You can look at the scrap of the coding and variables associated with anti reset windup in PIDincr.
dIntTermARW as hidden control_signal (0); // Incremental integral term after anti-reset windup
.................
// Calculate effect of anti-reset windup on integral term
If (OPClipping == Yes) Then
If (Abs(SolMode-1)>tol) Then // Not a steady state run
If (OPmans>100 and ((Action==Reverse and dIntTerm>0) or (Action==Direct and dIntTerm<0))) Then
// Output on upper limit and integral term is increasing output
dIntTermARW = max (-1,(101 - OPmans)) * dIntTerm; // Ramp integral term between +/- normal value
ElseIf (OPmans<0 and ((Action==Reverse and dIntTerm<0) or (Action==Direct and dIntTerm>0))) Then
// Output on lower limit and integral term is decreasing output
dIntTermARW = max (-1,(1 + OPmans)) * dIntTerm; // Ramp integral term between +/- normal value
Else
dIntTermARW = dIntTerm;
Endif
If (Abs(SolMode-1)>tol) Then // Not a steady state run
If (OPmans>100 and ((Action==Reverse and dIntTerm>0) or
(Action==Direct and dIntTerm<0))) Then
// Output on upper limit and integral term is increasing output
dIntTermARW = max (-1,(101 - OPmans)) * dIntTerm;
ElseIf (OPmans<0 and ((Action==Reverse and dIntTerm<0) or
(Action==Direct and dIntTerm>0))) Then
// Output on lower limit and integral term is decreasing output
dIntTermARW = max (-1,(1 + OPmans)) * dIntTerm;
We don't have external reset feedback logic in PIDincr We are considering in future release to use such features in multi-variable control.
Keywords:
References: None
|
Problem Statement:
|
Solution: Miscellaneous tags that are not updated by the Aspen Watch data collection tasks can be useful for displaying RT-OPT or other calculation results. FixDummyMiscTags.sql is a SQLplus query that can be helpful in creating these dummy miscellaneous tags. A procedure to create the tags is described at the top of the query file. Once the miscellaneous tags have been built, the query fixes the InfoPlus.21 records so that Aspen Watch does not attempt to do data collection for the tags.
Installation & Use
Open in SQLplus (Query Writer) and execute. Further instructions are given at the beginning of the query file.
This application tool has not been reviewed by Aspen Technology's Quality Assurance group, and it it not part of the Aspen Watch product; therefore, it is not officially supported by AspenTech.
Keywords: AppTool
References: None
|
Problem Statement: Aspen Watch performance monitor shows Run Time error 70: Permission denied, while adding new controller to Maker or updating an existing controller.
|
Solution: The error in subject Run Time error 70: Permission denied in Aspen Watch Maker appears mainly due to permission issues.
In this scenario, Aspen Watch performance monitor tool will not allow adding or updating the controllers in Watch Maker and the add or update options will be disabled/grayed out in tools.
The problem persists even after restarting Aspen watch Maker application.
TheSolution to this error is to start Aspen Watch maker by selecting Watch Maker and right click to select Run as administrator.
Now the add/update options will be available to be used and the controllers can now be added to the Aspen Watch maker list.
Keywords: Error 70
Run time error
Aspen Watch Maker
Permission denied
References: None
|
Problem Statement: Is there a way to generate a CLC or extract a list of vectors from Aspen Watch 2006?
The single vector extract is very cumbersome.
Either by planning, or because of problems with collections, it is necessary to extract model data from Aspen Watch. The vectors can be extracted one by one from the plot window of Aspen Watch Inspector, but this is very tedious, even with a small database, and prohibitive if the database is even moderate size. Is there a way to facilitate the extraction of data as vector files from the Aspen Watch database
|
Solution: In the .\AspenWatch\etc\sql\Demo directory are a couple of SQL scripts. CreateVectorFiles.sql and /or CreateVectors.sql.
For Windows 2003 found in: Document & Settings\All Users\Application Data\AspenTech\APC\Performance Monitor\etc\sql\Demo
For Windows 2008 found in: Program Data\AspenTech\APC\Performance Monitor\etc\sql\Demo
The content of the queries is fairly simple.
The ?Insert User specified parameters below? has to be properly set. Keep on mind that all the lines starting with ?- -? are comments, then those ones do not need edition. The email, as specified, needs additional configuration.
One example:
The next SQL section covers three main types of data: Controller Variables, PID Points and Miscellaneous Variables.
If nothing is specified the SQL will extract all the information available for the three types.
For example, if a single controller needs to be extracted, it would be like the following:
The CtrlId = AW_CTL_ID number is found in the Aspen Watch Maker.
And the section of PID Points and Miscellaneous Variables can be deleted or commented.
There are additional comments to explain required alterations.
In 2006,5 (and later) it is somewhat easier to pick variables, select history time range and export the history (still to vector files) to a zip file so you can download all from PCWS. This is in AW 2006.5 due out Jan.
Note also, there is a QueryDef record that you can configure to automatically zip up vectors files for a controller (all variables) and email it as a zip file daily. It's already there, you just have to activate it.
Keywords: None
References: None
|
Problem Statement: You want to change the logical device for some of your controllers, because some of the DMCplus controllers have been moved to a different computer.
|
Solution: Create the new logical device(s) which are configured for the new server. The same DLGP Service Name is fine, (even preferable) so long as the host name (of the logical device) is different.
Now with the new logical device in place (Let's say you created IODMCP3 and are moving from IODMCP) you can then go into IP.21 Administrator and make the changes merely by changing the names in the fields.
Go to AW_CTLDef, and find the controller you wish to change. The name will be <Controller Name>_<Logical Device Name>. So, if for example, you have a controller named Col5x3 which is assigned logical device iodmcp, the name of the AW_CTLDef record will be col5x3_iodmcp.
Highlight the record name in the scope pane (left hand pane), and you can see the fixed area fields in the contents pane (right hand pane). You will need to change two fields. The NAME field, and then down about 9 lines IO_DEVICE.
The name field will contain the name of the record, exactly as it appears on the contents pane. Change the name of the logical device (e.g. add a 3 to IODMCP) and hit enter. (If you simply move the mouse cursor, you haven't moved the change to the database. You must hit enter to make the change. Also YOUR change might not be as simple as adding a 3. Make the appropriate change for YOUR situation... ;-)
Change the contents of the IO_DEVICE field so it shows the new logical device. e.g. change it to IODMCP3 and hit enter. (as before, remember that you may not be changing to IODMCP3. This is just an example.)
Once the NAME and IO_DEVICE field have been changed, you must change the trigger query which initiates the collection for each controller. The trigger query is a QueryDef record that changes a field in the controller record to provoke a change of state activation. The record is of the form C0nT, where n is the ID number of the controller. (The ID number can be found in AWMaker, and can also be noted because it is in the prefix of all the records that pertain to that controller.
Change the query line in the query so that the record name portion of the tag is the same as the name to which you changed the AW_CTLDef record.
Monitor the controller in AWMaker to insure that the states changes to success after a cycle or two.
Keywords: Logical_devices.def
References: None
|
Problem Statement: Try to start InfoPlus.21/AspenWatch and tsk_h21_arcck fails with the message Time overlap [#2] in filesets nn, 0 where nn is the number of the fileset being complained about. This bug is triggered when there is an EMPTY reserved fileset in a repository. It is likely that
|
Solution: 121051 - Aspen InfoPlus.21 v2006 Server Update One (2006.0.1) The behavior was remediated inSolution 121407- Aspen InfoPlus.21 2006.0.1 Cumulative Server Patch (IP070706Z) - July 2007
Keywords:
References: None
|
Problem Statement: How can the user change the mass basis to mole basis (or mole to mass basis) for the OP value in the PID controller results table in Aspen Plus Dynamics?
|
Solution: When one creates a controller and connects the control signal from controller output (CONTROLER_BLOCK_NAME.OP) to a material stream, Aspen Plus Dynamics will display a window to allow the user to select one of available variables in a unit operation. The controller stream will connect to whatever input(s) that are defined as fixed. In order to change the basis, it is necessary for the user to change stream variable specification.
You can change the basis using the following steps:
a) Disconnect the control signal from the stream variable which you are trying to use as controller output (right click on Control Signal, select reconnect destination, and click on an empty part of the flowsheet),
b) Change STREAMS.Name.FR to fixed, and STREAMS.NAME.FmR to free as shown below.
c) Connect the control stream again and select as a variable STREAMS.NAME.FR. That should make the controller output connect to the mole flow rate instead of the mass flow rate.
You can also change the specification in another way:
a) Disconnect the control signal output,
b) Go to the STREAM.NAME configure form,
c) Change the Flow Basis to mole
d) Check the Fixed total flow check box,
e) Reconnect the stream's destination and select as a variable STREAMS.NAME.FR
f) Change STREAM.NAME.FmR to free in Stream specification to avoid situation when simulation is over specified.
Note: STREAMS.NAME and CONTROLER_BLOCK_NAME are only example names for the stream and PIDIncr controller block.
Keywords: Controller, Basis, PID, Aspen Plus Dynamics,
References: None
|
Problem Statement: Aspen SmartAudit fails with a pop-up error message that says:
Run-time error '521':
Can't open Clipboard
with a button labeled OK and when OK is clicked the application disappears.
This happens with remote desktop. Smart Audit opens OK. You are able to open and display a model. You select MVs and CVs for analysis. After pressing enter you get the error message described above.
This is caused by a Microsoft application entering a state where it doesn't function correctly. this application is rdpclip.exe. It is the application that makes clipboard information available on the local server as well as the remote computer being accessed by Remote Desktop.
|
Solution: TheSolution is to find this process in Windows Task Manager, and End process (Kill the process). then go to:
c:\Windows\system32 and find rdpclip.exe and double click on it to re-start it.
Once it re-starts Smart Audit should function correctly, until that process gets in a bad state again.
Keywords:
References: None
|
Problem Statement: How do I create custom PID configuration files in AspenWatch? Where can I find information on the procedure to configure custom PID configuration files for a non-standard DCS?
|
Solution: AspenWatch only has PID loop configurations for a limited number of DCS Cimio Server built-in to the DCS type configuration list for configuring the PID tags. The DCS type option in the PID tag configuration options is used to define the various PID loop parameters that re to be monitored. The DCS type configuration options is a combination of two file-
a) Configuration (.CFG)- This file holds the information regarding the various PID loop tags to be monitored for the DCS type in question.
b) Procedure (.SQL)- This file is an sql script that is used to configure the IP21 records for the various PID loop tags for the DCS type in question.
AspenWatch users have the option to configure up to three non-standard DCS types in addition to the standard DCS types already built-in the software. These are listed as a??CUSTOM1,a?? a??CUSTOM2,a?? and a??CUSTOM3a?? in the DCS Type option under PID Settings when importing tags in AspenWatch. Each of these three DCS types come with their own .CFG and .SQL file (found in the a??C:\ProgramData\AspenTech\APC\Performance Monitor\etc\sql\Pida?? folder for v7.3) that can be modified with the necessary custom information. The table below lists the configuration and procedure file names for the three custom DCS types.
DCS Type
Configuration File
Procedure File
CUSTOM1
AW_PIDC_CUSTOM1.CFG
AWP_PIDC_CUSTOM1.SQL
CUSTOM2
AW_PIDC_CUSTOM2.CFG
AWP_PIDC_CUSTOM2.SQL
CUSTOM3
AW_PIDC_CUSTOM3.CFG
AWP_PIDC_CUSTOM3.SQL
Configuring Custom DCS types
Follow the procedure listed below for creating a custom DCS type.
1. Select one of the three custom DCS type options available for editing. Browse to C:\ProgramData\AspenTech\APC\Performance Monitor\etc\sql\Pid and open the configuration file (using Notepad editor) associated with that particular DCS type.
2. Modify the configuration file by adding in formation for the various tag extensions to be monitored using for this DCS type. Note that you will need the information for a minimum of four parameters (Set point, Process Value, Output, and Auto/Manual Mode) in order to properly configure the PID loop. The format for adding the tags in is as shown below-
<Field_Name>A A A A A A A A A A A A A A <Data_Type>A A A A A A A A A A A A A A A <IO_Extension>A A A A A A A A A A A A A A A A A A A A A A A <Comment>
3. Once you have added all the information to the configuration file, save and close the file. Now open up (using Notepad editor) the procedure file corresponding to the same DCS type.
4. Edit this SQL procedure file according to the information in the a??SQL Procedure for Custom DCS typesa?? section of the AspenWatch help files.
5. Once you have modified the procedure file using Notepad, save and close it.
6. Bring up Aspen SQLplus from Start|All Programs|AspenTech|Aspen Manufacturing Suite and open the procedure file you just modified in Aspen SQLplus.
7. Execute the script by clicking the icon with a??!a?? (Exclamation) symbol on it. This will define the Procedure and IOGetDef records for the custom DCS type in IP21.
This completes the steps necessary to create and configure a custom DCS type to collect data for in AspenWatch. You can now go ahead and import the necessary PID tags using the custom DCS Type you just configured using the above steps.
Keywords: Custom DCS, AspenWatch, Configuration, PID loop tags
References: None
|
Problem Statement: How do I change text fonts in Aspen Dynamics?
|
Solution: There are three areas where you can change the fonts of your text in Aspen Plus Dynamics 1) Plot 2) Table 3) Flow Sheet. To change the fonts, Please go to Tools || Settings and click on fonts
You can change font type,size and style as needed.
Keywords: Font, Tools
References: None
|
Problem Statement: Aspen Watch 2006.5 with CP1 - Modifying a custom calc / cannot add a paramater as a constant value
|
Solution: We removed the CONST calc value type in 2006.5 CP1. The work around is to just edit the formula and enter the values directly as part of the formula.
Keywords: custom, calc, kpi, constant, value, edit, modify
References: None
|
Problem Statement: In some instances you may want to store the messages that appear when you export a file from Aspen Plus to Aspen Dynamics in a file to review later. This is particularly useful if you have a lot of warnings/errors and want to check them as you make changes to the file, or if your problem takes long to export and you need to do it again to review the messages again.
|
Solution: In your system set up the environment variable AST_SAVELOGFILE. Use the method appropriate for your operating system, as follows:
Operating System
Method
Windows 95/98
Set the variable AST_SAVELOGFILE to 1 in the autoexec.bat file and reboot your PC. The line in the autoexec.bat file should read SET AST_SAVELOGFILE=1
Windows NT4
Go open the System Properties window. You can open the System Properties window either from the System icon in the Control Panel or by right clicking the My Computer icon on your desktop and selecting Properties. Choose the Environment tab then define a system variable AST_SAVELOGFILE and give it a value of 1. Click Set and Click OK.
Windows 2000
Open the Sytem Properties window as for Windows NT then select the Advanced tab and click on the Environment Variables... button. Click on New... to add the setting for AST_SAVELOGFILE or Edit... to modify.
Windows XP Professional
Go to the Control Panel. If you see the Classic View then click on System and proceed as for Windows 2000. If you have the Category View click on Performance & Maintenance then on System and proceed as for Windows 2000.
Now when you Export/Send your Aspen Plus simulation to Aspen Dynamics, a file called runid.dpl will be created in the directory where you are running your simulation. Runid will be the same name as your problem name. This file contains all messages that you see in the window (if any) while exporting.
Alternatively if you have not got this environment variable set, you can still keep the messages as required by doing a right mouse click on the messages window, selecting Select All, then Ctrl-C to copy, and paste in your favorite text editor
Keywords:
References: None
|
Problem Statement: AW Reports cannot be generated on PCWS when you select an end date from in the past.
The following error appears when trying to do so:
“There is not enough history data accumulated to service this request. Please try a different time period and/or shorter duration for your report.�
|
Solution: This error usually occurs when IP21 does not have enough archive repositories to store data required for the request. To confirm the availability of enough repositories (and sizes), open IP.21 Administrator and navigate to InfoPlus21 | <AW Server Node Name> | Historian and confirm that you have free space in your file sets (check all three archives TSK_DHIS, AW_AGGH and AW_EVTH). In the following example the start date of the oldest file set in the AW_AGGH archive is July 12th 2013. Therefore, PCWS would not be able to obtain data to generate reports requested with an end time prior to this date.
In order to add new file sets to the archives, right click on the repository and click add file sets. Note that you can create multiple file sets at the same time.
The new file sets will not be available for use (grayed out) initially and require that the IP.21 Database is restarted for it to recognizes the newly defined file sets.
Keywords: PCWS, Aspen Watch Maker, History Reports
References: None
|
Problem Statement: How are RadFrac hydraulic and pressure drop calculations implemented in Aspen Dynamics?
|
Solution: RadFrac hydraulic and pressure-drop calculations in Aspen Dynamics depend on what option has been specified on RadFrac/Dynamic.Hydraulics form. This may be:
Simple
In this case only tray geometry needs to be provided - simplified hydraulic and pressure-drop calculations are used in Aspen Dynamics.
Rigorous
The user must create Tray/Pack rating section and check Updated pressure profile box on Tray Rating.Design/Pdrop form. The same rigorous calculations are performed as in the Aspen Plus steady state run.
In both cases the equations are already incorporated in the Stage model (submodel of Radfrac, under Dynamics/Submodels folder). The actual calculations depend on the hydraulics option specified in Aspen Plus, as explained above.
There is detailed information on this in online help, both in Aspen Plus and Aspen Dynamics (search under Tray). The (Tray Packing Sizing and Rating (TPSAR) feature is further explained in Appendix A of Unit Operation Models manuals - manuals can be downloaded from the documentation area of the AspenTech support website.
Keywords:
References: None
|
Problem Statement: Reactions in RCSTR can be specified with power law, LHHW law or user subroutine kinetics (template usrkin.f). Calculation speed for user kinetic can sometimes be improved dramatically by using the Aspen Custom Modeling language instead of external code.
|
Solution: The user kinetic interface can not make assumptions on which variables are accessed by the user, so in Aspen Dynamics we provide the same environment as in Aspen Plus. This means that the common blocks (like STWORK) are initialized to the correct values, which is done by calling a flash calculation. This flash calculation takes place for the calculation of the reaction rates, and the numerical derivatives required for the non-linear system reSolution.
The result is that during the dynamic simulation, Aspen Dynamics will do a lot of flash calculations, which are typically CPU intensive.
If the calculations in your subroutine are simple, and you know the Aspen Custom Modeling language (and you have a custom modeling license), you should consider the alternative of re-writing the calculations as equations in a modified UserReaction submodel (or a customized RCSTR model).
In one specific example, we have found that the simulation with the equation based kinetic was running in 30 seconds instead of 30 minutes, and it was more robust as well.
The gain in convergence robustness is explained by the fact that the derivatives of equations are calculated more accurately than with numerical derivatives when the kinetic is hidden in a subroutine.
Note that the same could apply for other models.
Keywords:
References: None
|
Problem Statement: How do I complete the upgrade when the installation database configuration aborts after the installation of Aspen InfoPlus.21 V7.3 CP2?
|
Solution: Definition record IP_AnalogDef and IP_DiscretedDef are modified with Patch V7.3.0.2 for Aspen InfoPlus.21 and database has to be upgraded or InfoPlus.21startup aborts.
Following is the procedure of upgrade database.
1. Start InfoPlus.21Manager using start as administrator option.
2. Execute Action | Upgrade Database
3. Select Typical and push next
4. Select following snapshot files
Source Snapshot : AWBACKUP.SNP
Output Snapshot : InfoPlus21.SNP
5. And push Complete button.
And, the database upgrade is done.
You have to use run as administrator option to execute Aspen Watch Install Database Configurationor it will abort.
Keywords: Aspen Watch Install Database Configuration, Upgrade Database
References: None
|
Problem Statement: Where can I find detailed formula of KPIs for Aspen Watch performance monitor?
|
Solution: For detailed understanding of KPI, the online help file, there is a help topic Built-In KPIs and Custom KPIs that list all the standard KPIs with a brief description and their formulas.
To access the help topics, from the Watch Maker, go to Tools -> Custom Calculations... menu, click on the KPI Help link in the upper-right area of Custom Calculations list dialog box.
Another good topic is Averages in KPI Calculations that is listed under How To: Aspen Watch Performance Monitor | Averaged in KPI Calculations
A couple of examples of built-in KPIs are provided below:
DEPACT refers to the Dependent Active Constraint Indicator in the DMCplus controller.
You can see the relevant help topic for this entry in the DMCplus Entry Dictionary (DEPACT).
DEPACT = 11 [UU] GAVE UP ON THE EFFECTIVE UPPER LIMIT.
DEPACT = 2 when the controller is planning to move the ramp to LRDPTG
VIO checks for limit violations (11)
CLC checks for limit constraints (2)
1. CLC = @IF(@EQ(DEPACT,2),1,0)*100 (percent time constrained at lower limit) - 2 [L] LOWER LIMIT.
The controller is predicting that it will control the value to the low limit (no violation). The KPI is showing the % of time the variable is constrained (controlled) at the lower limit.
2. VLO = @IF(@EQ(DEPACT,12),1,0)*100 (percent time lower limit violation) - 12 [LL] GAVE UP ON THE EFFECTIVE LOWER LIMIT.
This means the same as the Combined Status of '< Lo Limit'. The KPI is showing the % of time the variable is outside (violating) the lower limit.
More information will be available in KPI Template File which contains the exact formula used for these KPI calculation. The Template file will be available in Aspen watch server: C:\ProgramData\AspenTech\APC\Performance Monitor\Template
File: AspenAPCKPI_base.cfg
Make a copy of this file (so it doesn't get modified accidently) and open it using Excel (tab-delimited) to see all the KPI definitions. The template file can be used a reference to get an idea of how the KPIs are constructed.
In general, all the KPIs are designed to use values stored in standard DMCplus Entry Dictionary entries in the Aspen Watch records. In some cases, the values are summed across all variables in the controller. Additionally, custom KPIs can be created using these same values from the database, or from Miscellaneous or PID tags. The help in Maker has some additional discussion about this.
Keywords: Aspen Watch
KPI
References: None
|
Problem Statement: I loaded a file in Aspen Dynamics and the steady state run fails. What is wrong ?
|
Solution: Sometimes a steady state run does not converge if you try to solve for the steady state immediately after loading the file in Aspen Dynamics. This may sound surprising since theSolution that Aspen Dynamics receives from Aspen Plus is supposed to be already at steady state.
What happens is that Aspen Dynamics adds some controllers, and some of them (typically the level controllers) are set to automatic at time zero. If you run in dynamics mode for a couple of hours of simulated time, you will see the OP (OutPut value) and PV (Process Value) of the level controllers oscillate a bit.
After running a dynamic run until this oscillation is almost over, you can pause and switch to steady state - the run now converges more easily.
Keywords: convergence run type initialization
References: None
|
Problem Statement: How to model a tank which contains subcooled liquid in Aspen Dynamics?
|
Solution: If you have chosen Vapor-Liquid or Vapor-Liquid-Liquid as the valid phase for the block, vapor holdup will be modeled in Aspen Dynamics, even when your block contains only subcooled liquid. That's why you will get the following warning message when exporting the file to Aspen Dynamics:
The vessel contains sub-cooled liquid. The pressure in the vessel will be the bubble point pressure. This will affect downstream pressures. Vessel is initialised to be full of liquid.
To avoid this, you will need to specify Liquid only as the valid phase of the block. For liquid-liquid calculations, you should use a decanter block instead of a flash2 or flash3 block, as liquid-only will not give the correct results.
Alternatively, you can modify your flowsheet to add a feed stream of padding gas (e.g. nitrogen), so that there will be some vapor phase in the vessel (as it is typically done in plants). Typically you can specify just a small constant flowrate. This approach is recommended for pressure driven simulations.
Keywords: Subcooled liquid.
References: None
|
Problem Statement: In a flowsheet containing pumps with splitters downstream of them you may find a failure to converge when shutting pumps down. This convergence failure occurs in a pressure driven simulation when flows reach zero values and try to reverse.
|
Solution: Place valves on the streams between the outlet of the pumps and the splitters after the pumps. These valves should be check valves (the default for 10.2) as the pressure drop across these becomes negative as the pumps shuts down.
The pump efficiency should not be recalculated as the speed falls. Set the variable perf_curves(1).AffEE in the pump to 0. Recalculating the efficiency can lead to very high temperatures on the outlets of the pumps.
The efficiency for the lowest flow in the tabulated data should not be smaller than 0.2. Again this can lead to very high temperature at the outlet.
Keywords: Pump
Pressure Driven Flow
Convergence Failure
References: None
|
Problem Statement: What DCS are supported by AspenWatch for PID loop monitoring in version 2006.5
|
Solution: Here is the current list of supported DCS systems in aspenONE 2006.5 for PID loop monitoring:
FOXAPI
TDC3000
TDC3000_OPC
MOD300
CENTUM
DELTAV
SIEMENS_PCS7
ABB_PIDCON
EXPERION
Custom1
Custom2
Custom3
Keywords: None
References: None
|
Problem Statement: Which versions of DMC Plus are Aspen Dynamics and Aspen Custom Modeler compatible with?
|
Solution: Aspen Custom Modeler / Aspen Dynamics 10.2-2 supports use of DMCplus online 2.1 only.
Aspen Custom Modeler / Aspen Dynamics 11.1 SP1 supports use of DMCplus online 4.0
Aspen Custom Modeler / Aspen Dynamics 11.1 SP1 supports use of DMCplus online 4.1 with hotfix ADHotFix11.1.1.5.
Aspen Custom Modeler / Aspen Dynamics 11.1 SP1 supports use of DMCplus online 4.1 SP2 with hotfix ADHotFix11.1.1.7.
Aspen Custom Modeler / Aspen Dynamics 11.1 SP1 supports use of DMCplus online 5.0 with hotfix ADHotFix11.1.1.8.
Note that all DMCplus online versions mentioned here require Aspen License Manager 2.x
Aspen Custom Modeler / Aspen Dynamics 10.x requires Aspen License Manager 2.x
Aspen Custom Modeler / Aspen Dynamics 11.1 requires Aspen License Manager 3.x
Keywords: DMC Plus
online controller
dmcplus
References: None
|
Problem Statement: The way that liquid entrainment in Flash2 and Flash3 is specified in Aspen Dynamics is different to Aspen Plus when the dynamics of the flash vessel are included. This is because the Aspen Plus entrainment specification assumes steady state which is not applicable to a dynamic flash where the liquid and vapor flow out of the vessel are independent of each other i.e. the level and pressure in the vessel can vary.
In Aspen Plus, the liquid entrained in the vapor is specified as the liquid molar flow in the vapor stream over the total of liquid molar flow,
i.e. the molar flow through the liquid outlet + the molar flow of liquid that leaves via the vapor outlet.
For an instantaneous flash, Aspen Dynamics uses exactly the same specification. The variable ENTR is fixed and corresponds exactly to the Aspen Plus specification.
For a dynamic flash, another variable, LF_V, is fixed. LF_V is the fraction of the vapor outlet stream which is entrained liquid,
i.e. the molar flow of entrained liquid in the vapor outlet stream over the total molar flow of the vapor outlet stream.
LF_V could be manipulated or calculated with a flowsheet equation to implement, for example, a correlation giving the entrainment as a function of conditions in the block.
The equations which implement this can be viewed in the Flash2 model.
The initialization run should give exactly the same results as Aspen Plus. Strictly speaking it is not possible to compare the results for the dynamic simulation as Aspen Plus gives only a steady state
|
Solution: , but it may be important to understand the difference in the specification
Note that the relief vent port is always vapor.
Solution
Keywords: ENTR
VF_L
References: None
|
Problem Statement: After exporting the simulation from Aspen Dynamics, you may observe that sometimes Aspen Dynamics is having troubles to start the integration. Is there any advice on how to locate the problem?
|
Solution: The file exported from Aspen Plus to Aspen Dynamics should be very close to the steady state. Exceptions are if any warning message is printed during the export, in which case they may indicate the cause of the problem. Some models (PIPE and RPLUG) are different in Aspen Dynamics as they are discretized instead of continuous integration along the lenght of the pipe or reactor, and this can cause significant deviation from the steady state.
However, it can also be the result of a defect in Aspen Dynamics, in which case you should report the problem to support, so that we can try to fix it. But sometimes you cannot send the file, or you prefer to do a bit of investigation yourself. This is even more important if you have customized the models, or the control system, etc.
To check how far from steady state:
change run mode to Initialization and run the simulation
go to Tools, Variable Find
uncheck the option Algebraic variables
click on Find button
select one of the variable, press Control-A to select all
click on Table button, give it a name
on the table, do a right mouse click, and select to display the attribute Derivative
change the units of measurement (Tools, Units of measure) to Metric
We expect the derivative of the state variables to be small, around the numerical reSolution tolerance (1e-5), or at least much smaller than the value of the state variable. Large values of derivative indicate that the variable will change rapidely, which can cause problems with the integration. You can then try to isolate the blocks so that it is easier to investigate the problem.
Note that cumulative variables (QCum, FCum, etc) will not have time derivative of zero, as they integrate the heat flow or material flow.
You can also use this technique to find in a large flowsheet which variables are moving during a dynamic simulation, for example to identify some accumulation of components due to a recycle, etc.
Keywords:
References: None
|
Problem Statement: Are the CPU and Elapsed Time parameters for an Aspen Process Controller application historized in Aspen Watch?
|
Solution: Starting with V8.8 (CQ00559054) DELTAT and DELTACPU (the attributes that correspond to the CPU and Elapsed time values) are displayed in PCWS and automatically historized in Aspen Watch for all three APC types: FIR, MISO and MIMO.
Find below a screenshot of AW_DELTACPU and AW_DELTATIME of an Aspen Process Controller FIR (DMCplus) app.
Keywords: Elapsed Time, CPU Time, DELTAT, DELTACPU, Aspen Watch
References: None
|
Problem Statement: How to evaluate the mass fractions of components in a RADFRAC block, for plotting purposes?
|
Solution: This can be done with flowsheet constraints. The flowsheet constraint adds equations to the simulation. To evaluate the mass fractions you can use the following code:
Once you have compiled the code, you can use these variables for plotting, profile plot.
CONSTRAINTS
// Flowsheet variables and equations...
// calculation of mass fractions
n as integerparameter (description:number of stages);
ns as integerset ([1:n]);
xm(ns, componentlist) as massfraction;
ym(ns, componentlist) as massfraction;
MW(componentlist) as molweight;
n : blocks(B1).nstage;
call (MW) = pMolWeights();
for i in ns do
for j in componentlist do
xm(i,j) = MW(j)*blocks(B1).stage(i).x(j)/blocks(B1).stage(i).MWl;
ym(i,j) = MW(j)*blocks(B1).stage(i).y(j)/blocks(B1).stage(i).MWv;
endfor
endfor
END
xm and ym are declared as arrays to have the mass fractions in the liquid and vapour phase for each stage (the first index) and each component (the second index).
The procedure pMolWeights() is used to return the molecular mass of the components. As the global molecular weight of the phases is already available from the stage model, we do not recalculate them.
Finally the for loops do the conversion from mole fractions to mass fractions.
The example is attached
Keywords:
References: None
|
Problem Statement: What
|
Solution: method should I use in the PIPE model for a dynamic study?
Solution
In the PIPE model there are three options forSolution method: 1) Numerical Integration, 2) Constant dp/dL, and 3) Closed form.
In a detail dynamic study, the Numerical Integration method should be chosen in Aspen Plus. The Numerical Integration option in Aspen Plus uses the Gear method with adaptive step changes whereas in Aspen Plus Dynamics, the model is being solved using equidistance segments (fixed point). So the Profile calculation is more rigorous in Aspen Plus.
The Constant dp/dl method is selected when one wants to model the whole pipe as a simple tank or mixture. Closed form is not supported in Aspen Plus Dynamics
Keywords: Numerical Integration, Adaptive step, PIPE,
References: None
|
Problem Statement: In Aspen Plus 2006.5 the Dynamics button on the Dynamic toolbar is greyed out.
|
Solution: The Dynamic forms need to be enabled for layered product Aspen Dynamics. Go to the Tools | Options menu and select the Startup tab. Click on the checkbox for Aspen Dynamics to enable the forms.
Keywords: Dynamics form, enable form, layered product
References: None
|
Problem Statement: With the advent of the PCWS and reports that can be generated immediately via the web server, it is sometimes desirable to eliminate the reports that are generated on the AspenWatch server, both to save disk space, and to eliminate the calculation involved. Since the power of PCs is increasing so greatly, and disk space is so cheap, it might just be that the accumulation of these reports can be annoying, if they are not used.
Whatever the reason, if you wish to eliminate the reports generated by the server and placed in the controller directory, read on.
|
Solution: The performance report will not be run unless you have the string report in the command line parameters for the DMCwatch task (tsk_cl01-tsk_cl05).
State monitoring can be disabled by putting the character string nostate (must be lower case for this parameter) in the command line parameters for the DMCwatch tasks.
The daily and shift reports can be disabled by making their scheduled times undefined ?????.
In the InfoPlus.21 Administrator, you drill down to Definition Records, and from there to QueryDef. The report records are:
AW_Report_Shift1
AW_Report_Shift2
AW_Report_Shift3
Some of the older versions had an AW_Report_Daily, not AW_Daily_Schedule, which is something else entirely.
Expand the records and look at the #SCHEDULE_TIMES repeat area. There will be a SCHEDULE_TIME and a RESCHEDULE_INTERVAL. Highlight the SCHEDULE_TIME field, type a ??? and hit enter.
You might make note of what the schedule time is, in case you ever want to put it back.
Since you are intending to minimize the reports, the schedule time for AW_Daily_Schedule can also be set to undef or ?????. AW_Daily_Schedule only runs once a day, and usually at a time that shouldn't be busy, but still, it can be unscheduled.
AW_Report_Daily should not exist in any of the newer versions of AspenWatch, but if it does appear, it can be unscheduled too.
Keywords: Reports, AspenWatch, AW_Reports, AW_Report_Daily, AW_Daily_Schedule, PCWS
References: None
|
Problem Statement: Even after enabling the REAL TIME SYNCHRONIZATION option on Aspen Dynamics' RUN OPTIONS form, the simulation seems to run much faster than the real time observed on a wrist watch.
|
Solution: Lower the communication interval to 1 second (or 0.00028 hours)
The Aspen Dynamics models are set up to run with the hour as the time basis. The messages you see in the messages window reflect this. Also the communication interval is in the simulation engine time, not the interface time (see the Time Units list boxes.)
So for Aspen Dynamics, you need to set the communication interval to 2.778e-4 hours, otherwise the user interface will only be updated once an hour. Also you will only be able to pause the simulation once an hour as pause operates at the end of the current communication interval. If you find yourself in this situation and you want to stop a run, use the Run \ Interrupt option.
You can set the communication interval to a different value - the clock time taken per communication interval is the communication time in the units indicated, multiplied by the synchronization factor (rounded to the nearest second).
Change the Display Update to 1 second.
This controls how often plots refresh. It is a good idea to have this interval the same as the communication interval for real time simulations, though not necessary. The computational overhead is small. Note that tables update at the same rate as the communication interval.
In the middle frame, change the dimensional units for how the user interface should display time from hours to seconds
It is very important that these values are set correctly. The model units are described in the table below.
Product
Model Time Units
Aspen Dynamics
Hours
Aspen Chromatography
Minutes
Aspen Adsim
Seconds
Aspen Custom Modeler
ACM Library objects are in Hours. Can be user defined - must be consistent throughout flowsheet
If you write custom models for use with another product's library models, the time units must be consistent.
Check the Real time synchronization option. Leave the synch factor at 1.0 initially - lower the value to speed the synchronization, and raise it to slow the synchronization.
Note: This feature is intended for dynamic models that solve faster than real-time. Models with large numbers of equations that execute slower than real time will not be affected by enabling the above features.
Set the Synchronization Factor to its default value of Full.
Keywords:
References: None
|
Problem Statement: I have built my simulation in two parts, and now I want to reconnect them in Aspen Dynamics. What's the best way?
|
Solution: The easiest way is to use a MULT block (Dynamics library, in Manipulators model folder).
Create a MULT block (use the dot icon to keep your flowsheet tidy)
Connect the output stream of the first part of your flowsheet to the input port of the MULT block
Connect the input stream of the second section on the output port of this MULT block.
Finally, you need to free 2 specifications of this second stream, depending on how the stream was specified:
free the temperature and pressure, or
temperature and vapor fraction, or
pressure and vapor fraction
This works for all options, flow-driven simulation, pressure driven simulation and pressure driven simulation with reverse flow enabled.
Keywords:
References: None
|
Problem Statement: Aspen InfoPlus.21 Database Upgrade Wizard typical option does not work properly for the database for Aspen Watch. And, there is no example to show how to use the custom option with the database for Aspen Watch.
|
Solution: After
upgrading InfoPlus.21 to Ver.5.0, database for Aspen Watch has to be upgraded using InfoPlus.21Database Upgrade Wizard custom option not typical option.
1. Source Database : Old Aspen Watch snapshot file name
2. Optional list of records that should not be created or modifiled : leave blank
3. Base: AspenWatchBase.snp
4. Modify some records option should be selected and use '%ASPENWATCH%\etc\cfg\oktomodify.aw' file.
And, AspenWatch database will be upgraded properly.
Keywords: InfoPlus.21 Database Upgrade Wizard
oktomodify
References: None
|
Problem Statement:
|
Solution: AWView is an Microsoft Visual Basic (VB) application that provides pre-configured trends of Aspen Watch data. Features include:
Several plot types for CVs, MVs, FFs, PVs (miscellaneous tags) and PID loops.
A function to cycle through all the plots of a certain type (by selecting Cycle Tags in the tag name selection box).
The ability to open more than one trend window at a time.
Installation & Use
These instructions are also located in AWViewUserNotes.pdf, which is contained in AWView.zip.
Aspen Process Explorer must be installed before running AWView. You must compile the AWView source code (contained in AWView.zip) on the target computer using Microsoft VB 6.0 (or later). Creating the executable file on one computer and running it on another computer usually does not work because of incompatibilities with different versions of ODBC (however, you are welcome to download AWView.exe and try it). Ignore any warnings regarding OCX files when opening AWView.vbp in VB.
Before starting AWView, you must configure an Aspen Process Explorer server for the Aspen Watch database you want to access. When starting AWView, select the appropriate Aspen Watch Server in the DSN selection box under Connection Values in the ODBC Logon dialog box and click OK to connect to the database.
This application tool has not been reviewed by Aspen Technology's Quality Assurance group, and it it not part of the Aspen Watch product; therefore, it is not officially supported by AspenTech.
Keywords: AppTool
References: None
|
Problem Statement: Like any software, AspenWatch can exhibit behavior that is not what is expected or intended. This may range from inability to write to history, failure to collect because of stopped tasks or some other cause; inability to view certain data in Inspector, and many other symptoms.
For any given symptom, the causes could be many, but there is one cause that is so common as to warrant a specific
|
Solution: . That cause is a mis-match of the configuration files between the DMCplus controller and the AspenWatch database.
When AspenWatch is loaded with a controller, the engineer utilizes the controller configuration file (.ccf) and model file (.mdl) to teach the database what the controller looks like so it knows what data to gather from the DMCplus controller context.
If the controller is modified for DMCplus, and the information is not migrated to the AspenWatch computer, then AspenWatch is asking for information about a controller that is different than the one that is being run on the DMCplus computer. The types of failure this can cause are almost infinitely numerous. The only general thing that can be said about the resulting behavior is that you probably won't like it.
Solution
TheSolution is to insure that whenever there is a change made to the DMCplus computer, the configuration files are copied from the DMCplus computer to the AspenWatch computer and the controller on the AspenWatch computer is taught the new configuration.
To do this, for the affected controller (using COL5X3 as the name of the example controller):
copy the .ccf and .mdl file from the %ACODHOME%\app\COL5X3 directory to the %ASPENWATCH%\app\COL5X3 directory
Running AspenWatch Maker, run Update for that controller, now utilizing the newly replaced .ccf file, which will be referring to the newly replace .mdl file.
AspenWatch maker will parse the .ccf file, in a manner similar to the way it parsed the .ccf file when the controller was added to AspenWatch. It will compare the records that are in the database, with the records that are indicated by the new .ccf, and will resolve the differences by deleting the records that were created for records that have been removed in the new .ccf, and adding new records where indicated by new variables in the new .ccf.
The movement that will take place will utilize InfoPlus.21 mechanisms that preserve the history for the records which are kept.
The result will be that AspenWatch is asking for data from all the variables that exist in the DMCplus controller, and will not be asking for data from any variables that do not exist. It will also know where to put the values it retrieves in the InfoPlus.21 database.
Some additional information:
Every change that is made to a controller configuration does not REQUIRE that update be run from AspenWatch Maker, but running update should never hurt. If you are not sure whether or not it is necessary, copy the new files to the appropriate directory on the AspenWatch computer and update the controller.
In general, if the structure of the controller is unchanged, but the changes relate to tuning, limits, or entries like that, then the new data will be fed to AspenWatch from the DMCplus context along with the rest of the data, and the changes will be historized, and utilized in any pertinent calculations from that point on.
Another example of a change that should be acceptable is where an existing process, which is being controlled by DMCplus is being utilized for different products, or perhaps has scheduled changes in feed stock. The resulting changes in the .ccf file should only include changes in tuning, and very likely changes in the model curves which will be represented in a model file with a different name.
When the new .ccf is loaded into the DMCplus controller, the name of the new model file, is part of the data that is loaded with the new .ccf. this name is saved in the appropriate place in the context (the entry that represents the model name is, conveniently MDLNAM and is in the configure section of the .ccf), and the controller software will replace the curves with the ones in the new .mdl file. MDLNAM is one of the variables that AspenWatch collects each scan, so it will detect the change when it occurs.
When AspenWatch detects the change in the .ccf, and the name of the specified model file, it will try to find a model file by that name in the %ASPENWATCH%\app\<controllername> directory, and if it is able to find it, it will read it, and replace the old curves with the new ones from that model. If it cannot find the new model file, then there will be a problem with the calculations, and very likely the affected DMCwatch task will abort.
So? Make sure that any model file that may be utilized by the running DMCplus controller is copied to the %ASPENWATCH%\app\<controllername> directory.
Keywords: AspenWatch Maker
Update
References: None
|
Problem Statement: The MicroSoft Access database that is used for the AWEvents database in all the versions of AspenWatch up through AMS 6, seems to be quite fragile in this application. It will frequently become corrupt, and tasks which try to access it will be unsuccessful.
This might be indicated by error messages in Inspector, or in the tsk_aw01-5 .out files, or in the output lines of the QueryDef record AWEventMaintain.
|
Solution: To correct the situation, the AWEvents database must be compacted and repaired. There are several ways to do this. Here are the two most common.
The following steps can certainly be performed when the database is stopped (shutdown InfoPlus.21), but there has been some success performing the procedure with the database running. If you try the following with the database running, and you are unsuccessful, then try it after shutting down InfoPlus.21.
If you have MS Access installed on the computer, then you can compact and repair the database using the MSAccess Application. Simply double click on the database to bring it up in Access. Then go to the Tools || Database Utilities > || Compact and Repair database... to compact and repair the database.
If you do not have MS Access installed on your computer, go to the control panel. Then with Windows 2000 Windows XP or Windows 2003, go to administrative tools, and from there to data sources (ODBC). In Windows NT, go directly to Data Sources (OCBC). Double click on it, and in the resulting window, select the System DSN tab. Find the AWEvents name, and double click on it, or hightlight it and click the configure... button. In the resulting window, click the repair... button (Repair' also Compacts the database.) Follow the prompts until finished.
If you needed to shut down the InfoPlus.21 database to perform this procedure, re-start it now.
Keywords:
References: None
|
Problem Statement: How do I transfer stream results from Aspen Dynamics to Excel?
|
Solution: One approach is to create an Addin in Excel. This example has been created from a previousSolution which read results from Aspen Plus. The code has been improved to handle both Aspen Plus and Aspen Dynamics. You may find this tool useful to generate stream tables from Aspen Dynamics results.
To install the Addin:
extract the files from the attached zip file
copy them in any folder that is convienent for you
start Excel
go to Tools, Addins
click Browse and select the streams-ap-ad.xla file where you saved it
To uninstall the Addin:
start Excel
go to tools, Addins
uncheck the option near streams-ap-ad
remove the files from your computer
To use the Addin:
start your simulation (Aspen Plus or Aspen Dynamics)
start Excel
go to Data menu in Excel and select Import Aspen Dynamics Streams (or Import Aspen Plus Streams)
on the form that is displayed, click Open Simulation to select the simulation to which you want to connect
click the combo box Worksheet -- select <New Worksheet> to create a new worksheet with all streams -- select an existing worksheet to replace data (the stream names must be on first row, starting from the third column (C))
Aspen Plus and Aspen Dynamics don't list streams in the same order. If you wish to have streams in the same order, you can first get the results form Aspen Plus using the new worksheet option, then get the stream results from Aspen Dynamics using the sheet that has been created.
Aspen Plus orders the components as on component specification sheet, while Aspen Dynamics lists them in alphabetical order. Use Excel Sort feature to list Aspen Plus components in same order.
Aspen Dynamics may crash if the simulation is not already opened. (This problem is resolved by installing AD cumulative hot fix 5 or higher).
Finally, be aware that Aspen Dynamics calculates the vapor fraction only for feed streams. A value of 0.5 will be displayed for liquid-vapor streams flowing out of blocks.
The source code for this Excel Addin is of course included in the zip file.
Keywords:
References: None
|
Problem Statement: The default units of measurement (uom) for displaying all variables in a simulation is set by selecting the appropriate option from the available built-in UOM sets from the Tools | Units of Measurement menu. Often the standard UOM sets do not match the typical units of measurement used within your company. For example, many US companies typically use the units contained in the ENG built-in option set, but normally measure temperature in Deg C instead of Deg F. Changing the units of measurement for all instances of temperature on tables and graphs in a simulation can be tedious. Also, creating a custom UOM set to just change the units of measurement for few physical quantity types is time consuming. Is there a way to change only a few unit of measurements for key physical property types in a built-in UOM set and have those changes available for when I open a simulation in Aspen Plus Dynamics?
|
Solution: The UOM sets used in all Aspen Custom Modeler based products such as Aspen Plus Dynamics is set using visual basic scripts located in the following folder...
C:\Program Files\AspenTech\AMSystem VX.X\Bin
The file is OnSystemNewDocumentScript.vb. As indicated by the file name, this file is one of several files that are executed when a user double clicks a .dynf file or selects to Open a document from within the Aspen Plus Dynamics user interface. It is not recommended that you modify this file since the contents may be changed upon applying a hotfix or patch for the application. There is another file named OnNewDocumentScript.vb which can be modified by the user to contain any special startup commands, including creating new UOM sets or modifying a built-in UOM set created in the OnSystemNewDocumentScript.vb script. For example, the ENG UOM set has been modified in OnNewDocumentScript.vb to display temperature in Deg C instead of Deg F by including the following VB commands...
' Get the user specified UOM converter object
' examples
''''''''''''''''''''''''''''
' dim UOM
' set UOM = ActiveDocument.UOM
' bOK = UOM.AddPhysicalQuantity(VolumetricFlow, m3/hr, 12, 7)
dim UOM
set UOM = ActiveDocument.UOM
' Select for the default unit for display
bOK = UOM.DefaultDisplayUOM (ENG, Temperature, C)
Note that this is especially important when displaying variables in profile plots. Even if you change the units of measurement for a variable in a table that is to be displayed in a profile plot, the units displayed in the plot will always be the units in the selected UOM set. SeeSolution Document 124891 for details.
To see more details on these scripts and other automatically run event script,s open the Aspen Custom Model help | Automation
Keywords: units of measurement, UOM, profile plots, units, physical quantity type
References: from the Help menu in Aspen Plus Dynamics.
|
Problem Statement:
|
Solution: AWBackupHistoryAdmin.pdf (attached) provides an overview of the InfoPlus.21 history system and suggests procedures for archiving and remounting old history file sets. It also discusses backups for Aspen Watch.
AWBackupHistoryAdmin.zip (attached) contains the following files:
AWArchiveNotify.pdf - user notes for AWArchiveNotify.sql
AWArchiveNotify.sql - SQLplus query that sends an email message when the active InfoPlus.21 history file set shifts
AWBackupHistoryAdmin.pdf - see above
AWEmail.sql - SQLplus procedure for sending email (included in Version 1.2.0 of Aspen Watch)
AWPartialBackup.bat - batch file for scheduling AWPartialBackup.sql
AWPartialBackup.sql - SQLplus query that creates a zip file backup of critical Aspen Watch files (excluding old history file sets)
Blat18.exe - Public Domain Windows NT console utility that sends the contents of a file in an e-mail message using the SMTP protocol (included in Version 1.2.0 of Aspen Watch)
BlatReadme.txt - Readme file for Blat18
IP21251relnotes.pdf - InfoPlus.21 Version 2.5.1 Release Notes
ListHistoryFSTimes.sql - SQLplus query that creates a file containaing the FS_START_TIME and FS_END_TIMEs for all the InfoPlus.21 history file sets
SaveHistoryFSTimes.sql - SQLplus query that records the FS_START_TIME and FS_END_TIME for each history file set in a file in the file set path
Installation & Use
Start by reading AWBackupHistoryAdmin.pdf, and the nature of the other files will become clear.
This application tool has not been reviewed by Aspen Technology's Quality Assurance group, and it it not part of the Aspen Watch product; therefore, it is not officially supported by AspenTech.
Keywords: AppTool
References: None
|
Problem Statement:
|
Solution: Cle2misc.zip contains Cle2misc.exe, a command line program that will generate a TAB separated miscellaneous tag maintenance tool input file for Aspen Watch from a CLE file generated by DMCplus Collect.
Installation & Use
At the Windows command prompt enter:
cle2misc file1.cle
where file1.cle is the CLE file created by DMCplus Collect.
The output file will be named file1.txt and will contain all the tags from the CLE file.
This application tool has not been reviewed by Aspen Technology's Quality Assurance group, and it is not part of the Aspen Watch product; therefore, it is not officially supported by AspenTech.
Keywords: AppTool
References: None
|
Problem Statement:
|
Solution: CreateMiscTagInputFile.SQL is a SQLplus query that selects the information needed to create an Aspen Watch tag maintenance tool input file for the miscellaneous tags in an existing Watch database. Several manual steps are required to generate a properly formatted input file.
Installation & Use
See the file header for instructions.
This application tool has not been reviewed by Aspen Technology's Quality Assurance group, and it it not part of the Aspen Watch product; therefore, it is not officially supported by AspenTech.
Keywords: AppTool
References: None
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.