The Instant Pot is great for cooking a tough cut of meat until it’s fork tender. Chuck roasts are delicious! It can also take a lean round or rump roast and turn it into shoe leather in the same amount of time. Before experimenting with my own method, I checked in with some of my favorite websites and found this recipe. No worries if your Instant Pot doesn’t have a low pressure setting...mine doesn’t, either! Simply halve the amount of time the roast is cooked on manual or high pressure.
We cooked a 3.29 pound rolled rump roast on manual/high pressure for 3 minutes then allowed the Instant Pot to remain on the keep warm setting for 1 hour and 40 minutes. At that time we opened the lid and the temperature of the roast read 125 degrees. We removed the roast, tightly wrapped it in foil and allowed it to rest for an hour before slicing. My taste tester (and meat loving husband) said it tasted just like prime rib!
https://thisoldgal.com/pressure-cooker-roast-beef-instant-pot/