Detecting time "off"

Hi,

In order to being able to help you, you should provide the data, then it is possible to copy the data into Excel/Power BI and come op with some solution.

Is there  any point in time when you know that there is no event running, i.e. starting point. You could create a calculated column that counts number of start events before current time - number of stop events.

This is maybe a start for you, this will only work if you have the first start event, and then you might need to add some logic if you want to caculate for each day. And then there is a question what happens when Start and Stop event ocour on the same time?

Active connection = 
VAR t = Table4[Timestamp]

VAR starts = 
COUNTROWS(
    FILTER(
        Table4;
        Table4[Timestamp] <= t && Table4[Event] = "Start"
    )
) 

VAR stops = 
COUNTROWS(
    FILTER(
        Table4;
        Table4[Timestamp] <= t && Table4[Event] = "Stop"
    )
)

RETURN
starts-stops

Inactive sec. = 
IF(
    Table4[Active connection] = 0;
    VAR curTime = Table4[Timestamp]
    VAR nextStart = 
        MINX(
            FILTER(
                Table4;
                Table4[Event] = "Start" && Table4[Timestamp] > curTime
            );
            Table4[Timestamp]
        )
    RETURN
    IF(NOT(ISBLANK(nextStart));DATEDIFF(curTime;nextStart;SECOND))
)