In setting up a flow meter I noticed the the page for setting Pressurize Time actually has a “Settle time” label next to the up/down buttons. Classic cut/paste error, I’m guessing 
@jadwin79 - what “Settle time” is referring to is the time it takes for the water pressure in that zone to stabilize or settle after the zone starts.
On the previous page there is “Pressurize time” and “Settle time” as options. They refer to different things, but both have “Settle time” as the text label for the controls.
Pressurize time is the delay after a zone starts before the controller starts reading flow.
Settle time is the time after the zone is shut off before the controller takes a final flow reading to determine if water is flowing when it shouldn’t be, i.e., a leak.
One of these 2, if you set it to 0 will cause the flow meter to not function and you cannot calibrate. I scratched my head for an hour figuring that one out one day.