Process Controller Data Acquisition and Analysis

This is part of a series of tutorials. All tutorials up to the previous tutorial should have been completed.

Background

Process Controller can

Step One: Ensure that your Experiment is Set-Up

Make sure that all the valves and connections required to run your experiment are made. Your stamp box should look something like the figure below.

(insert picture of stamp box)

Step Two: Start the Experiment

Set your process controller to automatic operation and select "Add Chemical" as your first state.

Note: You may encounter problems after doing this such as the pump is not pumping or a valve is not working or there is leaking

You should try to fix any problems as they arise and troubleshoot the experiment. Don't worry if you spill water, but clean it up as necessary.

As the experiment is running check to ensure that things are working properly.

• Is the chemical stock tank gradually going down in volume over time in the "Add Chemical" state?
• In the "Settle" state, are both valves and the pump off?
• Did the water level decrease in the tank in the "Drain" state?
• After the "Drain" state, did Process Controller cycle back to "Add Chemical" state?

Step Three: Data Analysis

You only need to complete one full cycle of data collection. The next step is to to open the datalog and statelog that contains your file. Using the file directory where you logged your data i.e. N:\Courses\AguaClara\FlocTube fall09, open the excel file datalog and the statelog for the date of your experimentation.

Data Analysis in Excel

For this experiment we wish to plot the water level height in the tank over one cycle of the experiment (measured in elapsed time). Your first task is to create a graph of water level height in the tank over one tank cycle.

Follow standard format conventions:

• Do not include a title. If you want to describe the graph, put a caption underneath and begin the caption with "Figure 1." for example.
• Label your axes and put the units in parentheses.
• Eliminate any grid lines unless you are in log mode.

State log

Ensure that in your state log that you have cycled through the necessary states in process controller. There will be a time stamp of your team having done this.