Micro stalls in IBTS ROR

Has anyone else noticed that the instantaneous I-ROR values can go negative? I have been modulating roast power to keep the smoothed I-ROR values above 10 to avoid these, but can still get a few negative readings.

Does anyone else monitor this, or just ignore it?

Have a sample chart? Can’t see it here on R.W since I-RoR isn’t mechanized yet.


It doesn’t show up on the graph. In fact, if you don’t watch the left panel of the RoasTime screen, you’d never know it happened. I have enclosed a screen shot of the RoasTime window while the roaster is inactive. You can see the large 0.0 under I-ROR °F/min. Next time you roast, monitor this value. It varies much more than what gets plotted in the graph. I was watching during today’s roasts and the value went negative several times as I reached/passed first crack. I don’t know whether this is a real phenomenon that indicates the beans are cooling or if it is an artifact of the noisy I-ROR signal. Anyone else seeing this?

I’ve noticed this and choose to ignore it more like a noise. But the lag between the digital numbers and the actual curve is also noticeable.

I think I understand what you’re seeing. I believe it’s raw data as delivered by the roaster to RT3. Not really “raw” as it’s had some smoothing but RT3 does more.