power options , ( sutting down )

hi, new here

so please forgive me if this is in the wrong section ,

but i would to know about using some of the power options ,

while in the admin page , you have the power tab/section  ,

with in that you have the disk spin down , which seems to work , i can set the option to spin down and after 5 mins the disks will stop spinnig , great this seems to work ,

but the next option just below that is the  Power timer , this is  what im looking for an answer to :

i have tick the box ( unticking the disk spin-down   option)  tick all of the box with in the settings option so that thier are all gray out  some light some dark ,see pic

what im thinking i want to  happen is that the readynas will shut it self down ,

i have left it for a number hours about 4 hours , but the readynas is still active and i still can hear the drives spinning away and all of the blue lights on the front are still lit .

im i worng i thinking that the readynas will shut down , while i am trying to use this "power timer" option ?

i dont need to have the readynas on all of the time , just a few times a week  i will use it to stream a vid from my library of mkv files or add a file/data  to it.

thanks