24/7 usage of ac797 and sleep mode

Hi,

i want to buy a wifi hotspot that will be constantly plugged to the wall socket and wont go to sleep.

i have an irrigation controller that is suposed to be connected to the wifi but i'm not sure if it's always connected or connects every few minutes.  

i intend to buy a AirCard 797 but i saw in the manuall that it goes to sleep mode after 5 minutes of no internet usage.

is the AirCard 797 built for 24/7 usage and will it go to sleep even if it is plugged to wall socket?

thanks