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Run the Multiplexer Corrosion Potential standard technique by selecting Experiment > Multiplexed DC Corrosion > Multiplexed Corrosion Potential from the Framework™ menu bar. This initiates the following sequence of events:
1.Framework™ creates a Runner window, and the Multiplexed Corrosion Potential.exp script is run in this window.
2.The script creates the Setup dialog box and accepts changes in the experimental parameters. This dialog box allows you to specify the channels to be run, information concerning each channel, and global information about the entire experiment on all channels.
3.The script opens the electrochemical parameters file (SYSTEM.SET) and recovers the electrochemical system characteristics (βs, density , Equiv. Wt.) for each active cell from the file. If the script cannot open the file or find the System Name, the script warns you and then returns you to the Setup dialog box.
4.The script now opens the data file associated with each active Multiplexer channel to see if there are any problems with the composite (base plus channel number) file name.
5.The script now obtains the use of the potentiostat and Multiplexer specified during Setup and opens the data file using the Output name. It initializes the Multiplexer so that all the cells are in the off state specified in the script. If the potentiostat or Multiplexer are 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.
6.If Conditioning was selected in Setup, the local potentiostats in the Multiplexer condition all the Multiplexer channels. This includes both channels selected for data acquisition and cells that are not selected.
7.The script calculates the number of loops as Total Time divided by Sample Time. For example, a two-hour test with 5 minute Sample Time generates 24 data points.
8.The script switches the Multiplexer to the first selected channel. A two-second open-circuit-potential-versus-time curve is recorded on this channel’s cell. The last measured potential is recorded and placed into the Corrosion Potential versus time curve for that channel.
9.Step 8 is repeated for every other active channel.
10.The loop number is compared to the loops needed. If all the loops have been executed, the data acquisition loop terminates. The script relinquishes control of the potentiostat and multiplexer and closes any open data files.
11.If the test is not done, the script compares the script’s elapsed time to the next required Sample Time, and delays if necessary. After this delay it repeats the cycle though the active channels starting with step 8.