novice needs help with determining downtime

Hello,
I am somewhat of a novice to excel but lets say an occurrence that should happen every 1-2 minutes. If there is a departure from that I would like to know when that happened. Would there be a way to create a formula if so how would I do that? Below is an example, you can see there is a 6 minute stoppage from 6:37 to 6:43 I would like to have the cell highlighted when I import the data to excel to see that and record it.
thanks

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Hello and welcome to the forum.

Try something like this:

Highlight C2:C100 (or however far you want to apply the Conditional Formatting) > Conditional Formatting > New Rule > Use a formula
=OR(C3>C2+TIME(0,2,0),C1<C2-TIME(0,2,0))
Format: Fill color of your choice > OK > OK

This will highlight everything that is longer than 2 minutes.