Google for the manual.
Extending the entry time (EE timers) are in there, and it's always better to have the manual at hand rather than us telling you how to enter the programming menu's and what buttons to press.
Easier for yourself really,
You do mean that when you enter the building, the entry timer (beeps) runs, but it doesn't allow you enough time to get to the key pad before it goes into alarm don't you?.
If this is the case then it's not a hard change but a little detailed.
If for any reasons you run into any problems then we will try and help you sort it but as I have said have the manual at hand.
e manno, June 2013