User`s manual

Manual revision 016 Section 4: Deploying and Operating FastCAT SBE 49
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Acquiring Real-Time Data with ROV, AUV, etc. for Processing by Sea-Bird Software
Sea-Bird’s SBE Data Processing post-processing software typically converts a
FastCAT .hex file from Seasave to a .cnv file, and then uses the .cnv file in all
additional processing steps. A method to obtain data in the appropriate format
for SBE Data Processing, when data is logged to an ROV, AUV, etc. instead
of acquired with Seasave, is presented below. This method requires an ROV,
AUV, etc. to save all the FastCAT data (complete time series)
to a verbatim (unaltered) file, preserving the exact data format output by
the FastCAT:
1. Verify that the FastCAT is set to OutputFormat=3
(output decimal engineering units) and AutoRun=Y (begin sampling
when power is applied).
2. Begin sampling (turn on power to FastCAT).
3. Stop sampling (turn off power to FastCAT).
4. Recover the FastCAT data file from the ROV, AUV, etc.
5. Open the data file with a text editor (such as Wordpad, Notepad, or
Word). Delete any command lines (lines with S> prompt on them)
and any lines with partial scans. Save the file as a text (.txt) file and
close the file.
6. Rename the .txt file with a .asc extension (for example, test.rov was saved
as test.txt, and then renamed as test.asc).
7. In SBE Data Processing’s File menu, select ASCII In. Select the .asc file
as the input file, and enter the desired output (.cnv) file name. On the
Data Setup tab, enter the scan interval (0.0625 seconds for 16 Hz data,
0.125 seconds for 8 Hz data, etc.). Click Select Column Names,
and select:
A. Column 1 - Temperature [ITS-90, deg C]
B. Column 2 - Conductivity [S/m]
C. Column 3 - Pressure, Strain Gauge [db]
D. Column 4 - Salinity [psu] (if OutputSal=Y)
E. Column 5 - Sound Velocity [Chen-Millero, m/s] (if OutputSV=Y)
Click Start Process. ASCII In will create a .cnv file from the input .asc file
and the information on the Data Setup tab.
8. Use other modules in SBE Data Processing to further process and plot the
.cnv file as desired. Note that some processing modules require the
instrument configuration (.xmlcon or .con) file as well as the data file for
input. See Verifying Contents of Configuration (.xmlcon or .con) File in
Acquiring and Processing Data with Seasave and SBE Data Processing
above for a description of the configuration file, which is used in both
Seasave and SBE Data Processing.
Note
If OutputSal=N and OutputSV=Y,
select sound velocity for column 4.
Note:
You can perform additional processing
in SBE Data Processing even if you
already aligned, filtered, and corrected
for cell thermal mass using the
FastCAT’s real-time data processing
capability (ProcessRealTime=Y). For
example, you may want to remove
loops caused by pressure reversals
(ship heave), derive additional
parameters such as density, bin
average the data, or plot the data.