General Roasting Guide

 
 
Light
Medium
Medium dark
Development rate
10–18%
17–22%
>25%
Time
FC to FC+40s
End of FC to +1:30s
SC
Temp + FC (125 g)
4–8 °C
9–12 °C
+20 °C
Temp + FC (150 g+)
5–9 °C
11–14 °C
+20 °C
 
Default setting:
Start temp
183 °C
Power
60
Fan
30
Drum speed
70
Rule of thumb (normally):
Turning point should be around 25–40 s.
Begin – yellowing (“stage A”): 4:30–5:00
Yellowing – FC (“stage B”): stage A + 3:00
FC – finish (“stage C”): check table above
 
Procedures:
Warm up at 202°C for 1 min.
Set to 185 °C, let it reduce until 183–185 °C, hold for 1 min. Check if the air temperature is steady too.
Insert beans and adjust power to 60
When ROR = positive, adjust power to 90 to 100 (light roast = 100, medium roast = 95, dark roast = 90) OR the earlier the turning point, the lower the power is (e.g., 25s = turning point, power = 90)
From 2:00 to 2:30, reduce power by 5
When ROR begins to decrease, increase fan speed by 10 to make sure ROR steadily decrease (NOTE: increase fan speed may also increase ROR, keep an eye on ROR trend, reduce power by 5 if needed). Do this before yellowing (“stage A”).
After yellowing (“Stage B”) + 20s, reduce power (by a step of 5) for steadily decrease in ROR (e.g., from 90 to 60 gradually). Reduce only if there is an upward trend >10 s. DON’T LET ROR TO CRASH
Before FC (FC minus 10°C, typically ranged from 185–195°C):
Reduce power by 5 or 10, if there is any sign of ROR increase (=exothermic stage). However, don’t let power goes below 60.
Increase fan speed twice by 5 (total = 10).
When FC is in progress:
reduce power (reduce by 5). For washed bean: During FC, ROR may drop drastically. To fix this, increase power and rotation to 70+. 
If it still increases, drum speed = 70+.
If it still increases, fan = 50+.
Then, reduce power stepwise by 5 until it’s finished.
For medium and dark roast, final fan speed = [medium: 55, dark:60] + drum speed (70–80).
Check table above for ideal roasting levels.