Can't we do waitfor /T 180?
waitfor /T 180 pause will result in "ERROR: Timed out waiting for 'pause'."
waitfor /T 180 pause >nul will sweep that "error" under the rug
The waitfor command should be there in Windows OS after Win95
In the past I've downloaded a executable named sleep that will work on the command line after you put it in your path.
For example: sleep shutdown -r -f /m \\yourmachine
although shutdown now has -t option built in