Roasted 5 batches back to back today all at the same weight 775g and three different recipes based on each bean type that I’ve been working on.
After one roast I went back to examine the profile and make a couple adjustment to discover that one of my Power setting markers triggered about 5-7* late.
After my last roast I was confused by an unexpected pick up in IBTS readings in the final minutes of my roast only to discover afterward that my Power setting marker triggered almost 15* late.
I suspect that some of what you’re seeing is the accumulation of delays in comm between RT4 and the Bullet. When executing P/F/D commands from RT4, you have to: Click (or the Recipe issues a command) → RT4 sends to Bullet → process in f/w → change power → send send confirmation to RT4 → RT4 change the display.
I’ve seen the time lag between command and update in RT4. There have been changes implemented to minimize the delays but they still exist to some extent- it takes time to do the comm and ‘there is no free lunch’. In earlier RT4 versions I’ve seen accumulated delays of as much as 30 sec but that delay was in displaying the Time info… the P/F/D command had been executed ‘promptly’.
As an experiment you might try issuing commands from the control panel instead of RT4 so that you eliminate the 1st part of the accumulated delays using s/w generated commands. I suspect but don’t know that you’ll see a material difference in the time lags. For my part I use Recipes and don’t see any inconsistent lags. Time issues have all been resolved thru the Recipe commands indicating (I think!) that they are repeatable and related to bean behavior during the roast.