Time Limit Question

I set the time limit to 1 hr.  But he seems to have 1 hr on each machine, e.g., reached 1 hr limit on PC but have 1 hr remaining on a MAC when he logged onto it.  I thought time limit of 1 hr would be total rather than per machine.   Please advise if what I experience is supposed to be the case.   Fyi, I am checking out Norton Family so do not have a premier account.   Appreciate any clarification.   Thank you.