I would make a distinction between dried and fresh ravioli since they need to be cooked in a different way.
I would bring the water (ideally quite a large amount) to a rolling boil and salt it. Then add the ravioli and turn the burner down to half power such that the water remains hot (ca 90°C 190°F) but not boiling. In my experience using boiling water can cause the ravioli to rupture. Let the ravioli cook for the duration mentioned on the packet - start tasting one around 30s before package time is over to check if it's done.
Fresh Ravioli: Bring the water to a boil, salt it and turn off the burner before adding the ravioli. The problem with boiling water bursting the ravioli is more pronounced on fresh ravioli as they are more delicate. Add the ravioli to the water and wait for them to float - should take about 40s to 2min depending on how thick the dough is. The filling mostly just needs to be warmed up rather than cooked as it's made from eg. ricotta cheese or already stewed meat.
In general if you are worried about the timer I would recommend to rely on tasting and the look/feel of the pasta to discern if it's ready. I use the time on the box as more of a guideline since I find the time given on packets is often inaccurate anyway.