Excel ISERROR Function. The Excel ISERROR function returns TRUE for any error type that excel generates, including #N/A, #VALUE!, #REF!, #DIV/0!, #NUM!, #NAME?, or #NULL! You can use the ISERR function together with the IF function to test for an errors and display a custom message, or run a different calculation when found.
Meat is done when the temperature at its thickest point reaches the point at which it is safe to eat. That doesn't mean it's ready, though. According to USDA, ribs are done when they are 145Â°F internal temp, but they may still be tough. If you take them up to 190 to 203Â°F, the collagens and fats melt at this temp and make the meat more tender and juicy. Then they're ready!
Make sure the ribs are generously coated with a good BBQ rub. Here is a recipe for my rub which is great on ribs! 3 hours of smoking is the recommended time for pork spare ribs. If you are smoking back ribs you may want to smoke them for just 2 hours. Any more and you may find it dries the ribs out a bit too much. I have used hickory, apple, cherry, alder and maple woods with this method of smoking ribs.