Feedback Firmware 0.4.1. Perfect!

Started a new fermentation Sunday with a Lager at 12 degrees Celsius with the new 0.4.1 firmware with PWM support. The fermentation vessel contains about 50 liters. Just wanted all of you to see what the BrewPi can achive. And i must say that it is near perfect! The beertemp is steady between 12.00 and 12.06 which i believe is the resolution of the sensor. The fermentation has started which you see as the fridge setting / temp is lower than beertemp. The small “spikes” in fridgetemp is me opening the door to check the brew bubbling. You may also see that the fermentation picks up speed as the difference between beer temp and fridge temp is increasing.

As a side note you may have noticed my room temp is very low as my fridge is in a cold garage. It is actually heating to keep it at 12 degrees. My heater is a 200w heater which now runs at about 8% pwm to keep it at the correct temp. In other words about 16W of power is needed.

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@Blom1974, what kind of heater have you got? Doesn’t sound like a lightbulb-in-a-can, and not a blow dryer either. Mine is a heating pad which is much lower at full power than 200W and probably wouldn’t be able to provide enough heat for your current ferment.

I am using a 200W element (Frost Guard) and 2 120mm PC fans to get some circulation. 200W was way to much for the older firmware without PWM.

http://www.clasohlson.com/uk/Frost-Guard-and-Greenhouse-Heater/18-2865

Hi guys.
I have to agree. This FW works close to perfect. Did a Beer Constant with 2x23l buckets in the fridge. Then I changed to Beer Profile and did a test to raise temp 4 °C within 24 hours. The graph speaks for itself.

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Glad to see some positive results :smile:

I am pretty damn confident that the control with this firmware is much better than the 0.2.11. If it is not, some tweaking of the settings should make it better.

Refreshing the control algorithm tab to see what the algorithm is doing to tweak settings does not always work. I have identified the cause of this: the python serial port input buffer is only 4k and it it is not read frequently it fills up and data is dropped. Continuously reading the serial port in a background thread fixes it. Already working in the branch feature/backgroundserial. Will merge that into master soon.

Still Perfect ! And the fermentation picks up its pace…

If some of you wonder what the hell happened with my roomtemp it is just me starting a heating element in my garage.

Have to agree this FW is Perfect, No changes to setting and look at the results 23l Fermentation.

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:slight_smile: thanks for the positive feedback.

I don’t like the overshoot after the ramp down though, but that might be a hard one to fix. Because of the ramp down, the setpoint was continuously moving away. This was corrected by the integrator in the 2 hours from start of the ramp. It took about the same time to reverse this after the ramp.

Perhaps once we move profile management to the firmware instead of the pi, we can look ahead for changes in the setpoint.

Thanks for the information @Elco, putting the profile control on the Photon an not the Pi as you say would provide look ahead.

Keep up the good work it is very much appreciated.

I am just testing the current firmware on my Herms-build. Hell this is good stuff, it is holding the setpoints basically by 0,1°C! No overshoot, nothing to complain.
I also used the profile mode, with my rests programmed there. It is not perfect, but neraly perfect :smile:

So tomorrow I’ll do my first batch on this firmware and document it a bit. It is fun to control valves, pumps and everything from a computer, isn’t it :smile:

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