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If communication is successfully established, a window similar to the one below appears. Note that the status box is no longer empty and is now containing information on the module’s memory.
PC and Storage Module are now connected. The user can proceed with retrieving data files or other SM4M related operations. If the connection is not established successfully, a message will pop up as “Standard Prompt Not Detected”. Recheck the wiring connection and make sure that the Interface and the Storage Module are connected properly to the power source. Also recheck the COM PORT and then try to connect.
For ease of reference, the above-presented steps are listed in Annex 1.
5.2.3 Retrieving Raw Data Files from Storage Module During each data transfer from the datalogger to the storage module, the storage module stores this new data as a separate file. The storage module gives it automatically a new name or it could be changed as desired. This paragraph presents the user instructions for retrieving raw data files from the SM4M or SM192 Storage Module and storing them at a desired location (folder/directory) on the PC’s hard drive.
Step B1: Connect SM4M to PC and establish communication. See instructions in paragraph 5.2.2.
Step B2: Click the “Data” tab at the bottom-left. The below window appears.
Note that switching between the various task-specific sub screens (Setup, Programs, Data and Erase) has no influence on the contents of the Status Box.
Step B3: Mark the “Comma separated” option in the File Format select box. Import of comma separated ASCII files into MS Access has proven to be flawless and trouble free.
Step B4: Mark the “Auto Increment Name” option in the Auto Name Control select box. Each retrieved data file will get a name according to the format “DataXXX.dat” in which XXX is a number which automatically increments when a new file is down loaded.
Step B5: Click the file name in the File Naming Options location (in the current example this is Data031.dat). A box similar to Windows Explorer appears which allows the user to navigate to the location where he or she wants to store the retrieved data files. See the window below.
If the user has opted for the Recommended Directory Structure (see paragraph 4.2), data files captured from the
SM4M should be stored in the following folder:
C:\CAMPBELL\FILES\INPUT Step B6: Click the “Get New” button. This option collects all “new” data files from the SM192, i.e. all files not yet retrieved from the storage module in a previous down load operation. Each single SM4M data file is stored in an individual DAT file on the hard drive.
For ease of reference, the above presented steps are listed in Annex 2.
5.2.4 Pointers The Module Pointers area of the Status Box lists four different parameters, i.e. Free Space, Storage Ref. Pointer, Display Pointer and Dump Pointer. Each of which is briefly discussed below.
Free Space: As implicated by its name, Free Space concerns the number of free data locations in the SM4M.
Storage Ref. Pointer: The Storage Reference Pointer (SRP) points to the SM4M location where the next data value will be written.
Display Pointer: The Display Pointer points to the location which holds the first value which will be output in response to the ‘Get One’ or ‘Get New’ data button in the Data Control Section of the software.
The pointer can be set to any desired location by using the Display Pointer position box in the Advanced section of the data control status box, either by typing in the required location or clicking on the green arrow to move the pointer to successive filemarks. This option is used to re-down load data from the SM4M which has already been retrieved in a previous operation. This can be useful in case of data loss.
Data Retrieval, Processing and Final Storage in the Nile Basin Database PC208W Datalogger Support Software Dump Pointer: The Dump Pointer is an internal pointer used for keeping track of the current ‘start-of-dump’ for module-to-module data dumps. It indicates the first location from where new data should be collected. It is a function of the software to move this pointer after each successful data collection. Or it is the final storage location up to which data has been downloaded to the storage module in previous dump sessions and consequently represents the location from where data transfer will start in the default situation.
Especially the Display Pointer is useful if data is lost or corrupted during processing on PC. By manually setting back the Display Pointer (see above and the on-line help for the appropriate instructions), data files can be re-retrieved and re-processed, provided they still exist on the SM4M Storage Module.
5.2.5 Erasing Data on the Storage Module The user can decide to erase the information stored on the SM192. This applies both to data files and datalogger programs. However, since the storage module is put by default in ring mode, there is no need to erase data at any time. The moment the module is full, it starts overwriting the eldest information in the unit with new one, in this way never restricting ‘new’ information to be recorded.
If the user would decide that periodic cleaning of the storage module serves his or her purposes, for example to avoid confusion between two different field visits, the below text presents instructions how to do this.
To activate the Erase Control screen, click the “Erase” tab at the bottom-left of the SMS Window. The below presented screen will appear.
The Erase Control box contains three different options, each having self-explanatory names. Since it is advised to leave an uncorrupted version of the applicable datalogger program at all times in program location 8 of the storage module, the recommended option is number 1: Erase Data. No further user interactions are required.
5.2.6 Trouble Shooting Problem 1: SM4M does not respond by clicking the “Connect” button and is giving the message “Standard Prompt Not Detected”.
Cause: 1: Cables are not properly connected 2. Power supply 3. SC532A interface is not properly connected 4.
Problem with the COM Port or wrong SMS “Setup” Remedy 1.1: Check if the cables are connected firmly and if they are according to the following diagram Remedy 1.2: Check if the provided class 2 transformer is connected to a 110VAC power supply. For this purpose use a quality 220/240 to 110/120 converter. The SC532A interface needs 12 VDC to power up therefore the class 2 transformer has an output of 12VDC which is sufficient to power the interface. Do not use any other unreliable adaptor with an output of 12 VDC to power the interface otherwise the interface will blow and will stop working.
Remedy 1.3: Both ends of the SC532A interface have a nine pin holes.
The “PC” marked end of the interface should be connected to the nine pin computer cable while the “Peripheral” marked end of the interface should be connected to the nine pin SC12 cable.
Remedy 1.4: The computer cable should be, in most cases using either COM Port 1 or then COM Port 2.
In the SMS “set up” check first COM1 and if it does not work then check COM2. If the problem persists then check if the respective COM Port is not shared by any other software. In the SMS setup do not highlight/activate the “Via Datalogger” check box.
5.3 Report Utility of the PC208W 3.3 Software
5.3.1 Introduction The Report utility, also often referred to as Split, is used to separate individual meteorological parameters from the raw data files and put them into a format used in the various ‘target’ databases. It essentially performs the following operations (a) reads an input raw data file (b) extracts, splits and re-arranges data in accordance with the predefined criteria specified in a specific parameter file for each type of data; and (c) stores the result in an output file.
5.3.2 Processing Data from Met Station
126.96.36.199 General Each Automatic Meteorological Station established within the Project is equipped with 6 electronic meteorological sensors for measuring a set of six climatological parameters i.e. (a) solar radiation (b) air temperature (c) relative humidity (d) wind speed (e) wind direction and (f) rainfall. These parameters are measured at an interval of 5 minutes. At the same time the datalogger periodically records two station performance indicators: battery voltage and program signature. The METSTAT datalogger program has been designed to process all measurements and store in
its memory the following four groups of data:
• 5-minute rainfall time series with date and time of occurrence. To avoid excessive repetition of zero rainfall values and thus waste of datalogger memory, the 5-minute intervals during which no rainfall has occurred are omitted from the records.
• Hourly time series containing values of the following meteorological parameters: average hourly air temperature, relative humidity, wind speed, wind direction, and cumulative values of hourly solar radiation • Daily time series containing values of the following meteorological parameters: daily average, maximum and minimum air temperature; daily average relative humidity, wind speed and direction; and cumulative values of hourly solar radiation.
• Daily time series containing two station performance indicators – battery voltage and datalogger’s programme METSTAT signature. These are essential to monitor and maintain in good order for proper functioning of station’s datalogger and 6 meteorological sensors.
Data Retrieval, Processing and Final Storage in the Nile Basin Database PC208W Datalogger Support Software Due to the logger’s memory configuration, all four groups of data time series are written to the same storage area in the system’s RAM in the order of their occurrence (time of recording), and consequently downloaded from the datalogger directly via short haul modems or storage module to a PC as one single, rather unorganized raw data file. The role of the Report utility is now to extract, separate and reorganize the scattered recordings into consistent individual data blocks that can be appended to the existing database without too much further processing.
Report utility performs this operation through use of the so-called parameter files which have to be properly defined for each group of data – in this particular case for (a) 5-minute rainfall time series data (b) hourly meteorological data (c) daily meteorological data and (d) the station performance data. Each group of data is extracted from the same single raw data file by using a specific pre-defined parameter file and stored separately into an individual output file on the PC hard drive. At the same time the output data is displayed on screen during the programme run-time for a first visual quality check.
Table 2 presents the various files involved. 0XX stands for the data file’s serial number.
Each of the four file groups given in table 3 is dealt within more detail in the next four sub paragraphs.
188.8.131.52 Five – Minute Rainfall Data Only in case of a rainfall event, a cumulative 5 minutes rainfall value is stored into the logger’s RAM at the end of the interval. In contrast, for those 5-minute intervals in which the raingauge sensor has not registered precipitation (i.e.
the rainfall values are equal to zero), the zero rainfall values are not stored to avoid loading the datalogger memory with meaningless information. Consequently, the 5-minute rainfall data consists of a 5 minutes time series in which a cumulative non-zero 5-minute rainfall was registered by rain gauge sensor. Consequently, the gaps in the recorded time series indicate dry periods without rain events at the measurement site.
Procedures for the extraction of 5-minute rainfall time series data from a raw input file and storing the result in
an output file for final processing is described in the following text:
Step C1: Activate Report by clicking the Report tab on the PC208W toolbar. The below screen appears.
Step C3: Navigate to the location on hard drive, which contains the parameter files. This is “C:\CAMPBELL\FILES\ PARAMETR” if the Recommended Directory Structure is used. Highlight the file “metrain.par”, as shown on the window below. Click OK.
The title bar on the Split window now indicates the name of the open parameter file.
Step C4: Activate the Input File(s) sub-window and select the Input Data File. To this end click “Browse” in the Input Data File box and navigate to the location (folder/directory) on hard disk which contains the raw data files. This is pictured in the following screen. Highlight the appropriate file and click OK.
Step C5: Switch to the Output File sub-window by clicking its tab at the top-mid of the current Split screen. The below window pops up.
Step C6: In the File Name text box of the Selected Output File sub-screen, type in the name of the appropriate output file. Apply the following naming format: “metrnXX.txt” Make sure that the XX - serial number of the output file – is the same as of the respective raw data file. For instance, give the name “metrn31.txt” to the output file if it is being extracted from “data031.dat” raw data file. Click
OK. This process is presented in the windows given below:
Step 7: Finalize the routine by selecting Go from the Run menu. The results, as presented on computer screen, are
similar to the window given below:
For each five-minute interval in which rainfall has been registered at the station, the following information is extracted from raw input data file: station datalogger-ID, year, date and time and cumulative five-minute rainfall values. The first four values (i.e. ID, year, date and time) guarantee that each array is uniquely identified.
The associated output file is in comma separated ASCII format. This is shown below for the output file “metrn31.