Updated: January 1, 2018
I recently installed an HTRI control board in my HotTop and have really enjoyed the improved control I have over the roaster.
On a stock 8828-B (my base-model), the highest level of control one has is a choice of four fan settings and ten heater settings. With the use of the HTRI board and Artisan Roaster Scope, the level of control increases substantially.
One of the things I teased in my post about installing the HTRI was something I call conditional automation. Using Artisan, proper thermocouple (TC) placement, and an HTRI device, one can create a set of alarms in Artisan to automatically react to certain conditions based on time, temperature, and optionally the satisfaction of previous alarms.
To help illustrate the functionality, here are a few examples of alarms one could create:
Let's say you routinely hit 300°F around the 4-minute-mark on a given bean and that has become a benchmark for you to know if you are on track to repeat a previous, desirable roast. You can look at previous, successful roasts and see that you're routinely at 275°F around the 3-minute-mark, which means you'll likely hit 300°F in four minutes. You can create an alarm in Artisan to increase the heat a bit to try to make up time. The basic alarm would be:
3:00 from CHARGE, BT below 270°F, Slider Power 100
That alarm will only trigger if the BT is below 270°F three minutes after the registered CHARGE event. If those conditions are matched, it bumps the power up to full.
As another example, suppose you have a bean that routinely starts producing heat (going exothermic) shortly after the ET rises above 401°F and you want to anticipate the rise in temperature by decreasing the amount of heat you add to the environment in order to maintain a steady decline in RoR, a la Scott Rao's recommendations, you can configure a set of rules to gently reduce the heat after ET passes 401°F such as:
From CHARGE, ET above 401°F, Event Button 6
This alarm takes advantage of a new feature in Artisan, which allows one to create custom events in the form of buttons that change the fan or heater by X. Once you have created those buttons, you can activate them via alarms.
I stack three or four of these types of alarms on top of each other, at increasing trigger temperatures in order to gently and slowly decrease the amount of heat added to the environment over time.
For this example, button number 6 would have the following settings, which decrease the current heat power by 3:
With the combination of condition-based rules and roaster automation, it's possible to create a program that goes beyond simply hitting time and temperature set points and instead actually reacts to time and temperature conditions currently present within the roaster.
For more information on buttons, alarms, and sliders within Artisan, watch my instructional video:
Updated: January 1, 2018; Embeded Youtube video
Continue Learning: Looking for more how-to articles or articles about roast science? Then check out this page for more!