The interval scan is the 3 seconds you have wired to the Wait (ms) function. The wiring of the current time in seconds to the chart is incorrect. You need to write the wait time to the chart's Multiplier property. The start time would be wired to it's Offset property. Look at the example called Real Time Chart.
In order to save all of the data when the loop finishes, you would need to enable autoindexing of the array. Might be better to place the write inside the loop. You might want to get the current date/time as a string and convert the numerics to strings and use the string type of the Write to Spreadsheet File.
p.s. Move your Initialize and Close functions to outside the loop. You do not want to do either with every iteration of the loop.
