Time.Second Function in Power Query
The Time.Second function in Power Query is used to extract the seconds component from a Datetime/time value.
Syntax
 Time.Second(dateTime as any) as nullable number 
The function has the parameter dateTime as any. It returns a number representing the seconds part of the time.
Example: Extract the second component.
Power Query M
let
    Source = Time.Second(#time(20, 54, 25))
in
    Source          The output of the above code is 25.