Thursday, November 24, 2016

Area under the Curve (AUC)

The idea that the area under the temperature curve could be an indicator on how much total energy the beans might have receive during the roasting process popped up already some years ago. While the rate-of-rise (RoR) of a temperature curve, calculated as the first (discrete) derivation, gives the current "speed" of the temperature increase and allows to predict the future, the area-under-the-curve (AUC) describes the past.

PID Control

A PID controller is a control loop feedback mechanism commonly used in industrial applications. – PID Controller, Wikipedia

Monday, October 10, 2016

Die Zweite Deutsche SCAE Röstmeisterschaft 2016

The second German SCAE coffee roasting championship took place last week on 5-7 October @Probat in Emmerich. It followed very closely the protocol and style of last year's roasting championship.

Sunday, August 14, 2016

More Alarms

Support for alarms has been around for quite a while and is in heavy use by some. More recently I got asked how to define an alarm that should be triggered 30s after the FCs (First Crack start) event.

FZ-94 (4) – Taking Control

Now that Artisan can talk to the drive controllers, it is not only possible to read the drive speeds, but also to control the drive speeds. However, that needs some further configuration changes on the drive controllers as well as some additional setup on the Artisan side.

Friday, August 12, 2016

FZ-94 (3) – Connecting the Drives

The FZ-94 comes with two Delta VFD-L drive controllers often referred to as frequency drives. One controls the drum speed, the other the air flow via the fan speed. Both are operated manually via a dial. While Artisan can log roasts automatically by reading the three temperature values from the machine via its RS485/MODBUS connection, the drum speed and air flow, both of which have a considerable influence on the resulting roast, have to be manually marked via some user defined buttons or sliders.

Videos: Curve Controlled Roasts with FZ-94 and Artisan

See also:

The video below may be a little boring for some because I did not cut footage from it to skip any part that may be uneventful. Do slide back and forth at will to see / ignore any part you want.