How can I format a cell to be "hours:minutes:seconds" without Excel treating
it as a time of day?

When I enter "2:24:38" Excel treats it as "2:24:38 AM".

My goal is to have Excel treat the times entered as an "elapsed time" so to
speak. Then, at the bottom of the column, I'm looking to add a total of all
the elapsed times in that column.

How do I accomplish that?

Thanx.