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<< Click to Display Table of Contents >> Navigation: Experiments > I - Electrochemical Frequency Modulation > Techniques > Multiplexed EFM Trend > Multiplexed EFM Trend - Experimental Sequence |
Run the Multiplexed EFM Trend standard technique by selecting Experiment > Electrochemical Frequency Modulation > Multiplexed EFM Trend from the Framework™ menu bar. This initiates the following sequence of events:
1.Framework™ creates a Runner window, and the Multiplexed EFM Trend.exp script is run in this window.
2.The script creates the Setup dialog box which becomes the active window and accepts changes in the experimental parameters. This Setup window remembers the experimental settings from the last time this script was run. To restore the parameters to the values defined in the script, click the Default button.
3.The script now obtains the use of the potentiostat specified during Setup and opens the data file using the Output name. If the potentiostat is in use or the file cannot be opened, the script returns you to the Setup dialog box. The file header information is written to the data file. This information is written to the file prior to data acquisition. If the experiment is aborted, the file contains only this information. This header information includes:
•Tags identifying possible analyses.
•The current time and date.
•A list of the Setup parameters.
4.The script opens the data file associated with each active Multiplexer channel to see if there are any problems with the composite (base plus channel number) filename.
5.The script now obtains the use of the potentiostat and Multiplexer specified in the script or in the Setup dialog box. It initializes the multiplexer so that all the cells are held at open circuit when they are not being measured. If the potentiostat is in use or the Multiplexer cannot be opened, the script returns to the Setup dialog box.
6.If the elapsed time for this experiment is greater than the Total Time, the script complains and returns to the Setup dialog box.
7.If you selected Conditioning in Setup, the local potentiostats in the Multiplexer are used to condition all the Multiplexer channels. This includes both channels selected for data acquisition and cells that are not selected.
8.The script switches the multiplexer to the first selected channel. A complete EFM experiment is run on this cell. An optional Initial Delay is performed prior to each scan. In all cases, Eoc is measured prior to the scan.
9.Finally, the actual EFM measurement occurs. The two-frequency composite signal is applied to the cell and the current is recorded. At the conclusion of the measurement, the potentiostat cell switch and multiplexer channel are turned off.
10.The script calculates Icorr, Corrosion Rate, Tafel Constants, and Causality Factors. The resulting data point is appended to the data file for that channel and the data file is closed.
11.Steps 8 through 10 are now repeated for every other active channel.
12.After all the channels have been run, the script checks the repeat cycle time and delays if necessary. After this delay, it repeats the cycle though the active channels starting with step 8.