Difference between ibts and bt


I Installed RT4.0 yesterday. Today i do a roast.

Is it normal that i have ibts 220 degree and after 20 min only 160 degree of BT ? 60 degree difference is much … i have not got the signal to charge with beans

That looks pretty normal. On my R1 charge signal usually comes around 24-25 min mark, for the fist roast. I am not entirely sure how the algorithm works, because I see ± 3-4C BT difference on the fist charge signal, meaning sometimes it signals on 163C and sometimes on 166C, for 220C PH temperature.