Summation of Time Stamps

Excel file has a running time stamp (00:00:00 up to 23:59:59). Three columns where values for certain rows oscillate between 0 and 1023, nothing in between those two numbers, just a 0 or 1023. What I would like to do is sum up the time elapsed for when a certain column reads 1023. I've tried SUMIF, but that simply adds up the hrs, min, and sec. I need to add up the time elapsed between the a column changes to 1023 and when it changes back to 0. It happens rather often.

Looking for a formula where it will take the end of the time elapsed (i.e. when a value changes from 1023 to 0), subtract it from the beginning (i.e. when a value changes from 0 to 1023), and then repeat that for an entire column. Haven't had much luck so far.

See attached workbook.