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Run the Multiplexed Potentiostatic standard technique by selecting Experiment > Multiplexed DC Corrosion > Multiplexed Potentiostatic from the Framework™ menu bar. This initiates the following sequence of events:
1.Framework™ creates a Runner window, and the Multiplexed Potentiostatic.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 obtains the use of the potentiostat and Multiplexer specified in the script or in the Setup dialog box. It initializes the Multiplexer and potentiostat. If the potentiostat or Multiplexer are in use or the file cannot be opened, the script returns you to the Setup dialog box.
6.If Conditioning is enabled in the Setup, all the channels are simultaneously conditioned. This includes both selected and non-selected channels.
7.The open circuit is measured for all selected channels. This open-circuit potential is used to calculate initial and final potentials versus the reference electrode. The file header information is written to the data file for all selected channels. 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.
8.All active channels in the Multiplexer have their local potentiostats set for the initial potential. The inactive mode for all selected channels is set to Local Potentiostat mode.
9.The data acquisition loop begins. If the time is greater than the time at the initial potential, the final potential is applied to all active cells. If the time is greater than the total experiment time, the script goes to step 10. The system potentiostat is switched to each active cell in turn. A short current-versus-time curve at the appropriate constant potential is recorded on this cell. The average current value is recovered from the curve and written to the result curve. After the last active cell, the script waits until it is time to take the next data point. It then runs through the data acquisition loop again.
10.The script waits for you to click the F2-Skip button. When you do, it closes everything that is open and terminates itself. The local potentiostats remain on at the conclusion of the experiment.