My mom finds that having to come back into the kitchen every 5 minutes is annoying and we would like to extend that time out much longer so she doesn't have to be attentive and hang around the kitchen.
Well the short answer in no, the iGuard does not allow the timer to extend past 5 minutes. This is the exact reason that the iGuard exists. People will typically turn the stove on and wander away with good intentions to return to the kitchen right away. Distractions often win out over our "best intentions"—and when they do, thats when a fire will start. A lot can happen in even 5 minutes, so thats is why we do not allow the auto shut off time to be extended past the 5 minutes.
However, the 5-minute timer doesn't give you JUST 5 minutes. The timer works with the presense sensor. As the timer is counting down and the iGuard sees motion, the timer gets automatically reset back to 5 minutes. If you are attentive to your cooking the iGuard will allow the cooking to continue. Its only when you are gone for the full 5 minutes, that the timer will time out and then the stove element(s) will be de-energized. And if you return within 15 minutes, the iGuard will re-energize the elen=ments so you can continue cooking withour pressing any buttons.
Having said all that there is also an Extended Cooking timer that allows for longer periods of uninterrupted and unattended cooking for doing things like a roast or simmering a stew but there is NO auto shut-off safety with that feature. It is intended for proper and intentional use and if you feel that someone will abuse this feature and just use it so they don't have to be attentive to their cooking, then you can lock this extending timer out so it can't be used. This will require the cook to allow for the iGuard to step and and help protect the home from their "best intentions".
The whole idea behind the iGuard is to prevent fires and to not create situations that would cause fires.