Ghost in the machine?

[RickGroszkiewicz]

I had a frustrating roasting experience today.

I was roasting a coffee on my Hottop B-2K+ and it dropped the beans right before I got to first crack. I trashed the coffee, then tried again after the roaster cooled down. I'm completely baffled, because it dropped the beans before first crack again! This time, I saved the beans and re-roasted them on my old Hottop TC4C.

I had success roasting other coffees on both of my Hottop roasters.

[RickGroszkiewicz]

I looked at the artisan log files, but did not see anything notable. I have attached them in case anyone wants to take a look.
Ethiopia Sidama Bensa Keramo 2022 - BAD-2.alog.txt
Ethiopia Sidama Bensa Keramo 2022 - BAD-1.alog.txt

[poundy]

where's your settings file? Makes no sense to look at just roast files without knowing your settings.
Whats the history of you and this roaster? Version/s of Artisan? Something like this doesn't just "go bad" it's usually a deliberate change that you've made that has an unintended consequence, or a misconfiguration when using something for the first time.

[RickGroszkiewicz]

I have over 400 roasts with my Hottop B-2K+ and over 1400 with the Hottop TC4C. The only change I made this year was upgrading to artisan version 3.1. I have roasted this coffee many times before with no problems.

I have attached my settings file for the B-2K+ roaster. You can get a quick overview of my settings here:
https://softwarepolish.com/albums/Artisan%20software%203.1%20-%20Linux%20Mint%2021%20-%20%20Hottop%20B-2K/index.html

artisan-settings-B2K-04-03.aset.txt

[poundy]

How recent is the 3.1 update to these two "failing" roasts? Are they the first of your roasting on 3.1?

As Terracotta says below, you have autodrop on. Personally, I don't use it as if you get spurious reading/s (I used to have pretty poor thermocouples with low resolution and slow update rates) you can easily have something like this happen. I don't know if there were changes in 3.1 that are related to autodrop sensing specifically, but there are several items in the release that mention drop and autodrop . See https://github.com/artisan-roaster-scope/artisan/blob/master/wiki/ReleaseHistory.md for the details if you're interested. From the raw data in the first log I looked at there didn't seem to be any obvious reason the samples would trigger autodrop but I am not familiar with the code to know.

[RickGroszkiewicz]

I have done 15 roasts on my Hottop B-2K+ with artisan 3.1. I never understood the purpose of auto-DROP for my Hottop, and that setting should have been turned off.

[Terracotta-6]

[RickGroszkiewicz]

You are correct - thank you!

[MAKOMO]

Seems not to be the AutoDROP feature. The data around the event looks ok. Very noisy, but nothing that should trigger the AutoDROP. Could it be an alarm that triggered? Sharing the Artisan setup you used here could help?

[poundy]

Certainly the data isn't very "smooth". This is much like my TC4 emulated device I used to use and mentioned in my earlier post. You can see that the data sampling rate you have in Artisan is probably too fast for the resolution and sampling rate the device can keep up with, so you end up with lots of "stair stepping" at the sampling points - which leads to a very choppy ROR, where it goes from 0 to 20 or 40. This was exactly the reason I never used autoDROP, so yes, turning that off will fix the premature end of roasts (but not your data).

[RickGroszkiewicz]

@roasterdave I'm confused. The only dip is in delta ET - why would that trigger a DROP? Going farther back, I see a dip in BT at sample 351. Note that my artisan shows degrees in Fahrenheit, not Celsius.

[RickGroszkiewicz]

@poundy My delta ET and delta BT data from the Hottop B-2K+ looks like garbage compared to the TC4C. Do you have any suggestion how I can improve that?

[roasterdave]

I'm confused. The only dip is in delta ET - why would that trigger a DROP? Going farther back, I see a dip in BT at sample 351.

Here are graphs of your two bad profiles zoomed in on BT with all smoothing turned off. Notice how BT is increasing then declines for multiple samples before rising again. This signature fools autoDrop. BT ought to be increasing through this period. It may look like a subtle change but many roast machines have actual DROPs with this signature. Thus when the BT signal behaves this way it is best to manually mark DROP.

[Terracotta-6]

与 TC4C 相比，我来自 Hottop B-2K+ 的 delta ET 和 delta BT 数据看起来就像垃圾。您有什么建议可以如何改进吗？

The inherent characteristics of coffee roasters: Excessive temperature fluctuations in BT mixed with electronic noise cause the Delta BT to be uneven and unattractive, which does not affect the flavor of coffee roasting.

autoDROP is not intelligent. It has relatively high requirements for the performance of coffee roasters. Only under such conditions is autoDROP possible. As shown in the attached figure: