I had a late start Brewday to do a Treacle Porter might double up for the NCB January event but Maybe not as I don’t intend going..last time the tasting of 22 beers wasn’t that enjoyable..!
Any way back to the BrewDay.
I think the Gremlins have taken up residance !My automation in the BrewShed just didn’t play as nicely as it should, the Raspberry Pi on the Herms System froze / crashed and so I reset it. but towards the end of the mash noticed the temperature wasn’t rising but was falling ! a quick SSH into the Pi and the time was now -1 hour out even though the time zone was London…a quick manual intervention and set it to mash out temp of 75.5 to lock the sugar profile.. saved the brew…
Whilst I was in maintenance mode back up at the house I thought I might as well update the fermentation Brewpi with the integrated Tilt Hydrometer mods to the latest 0.4.4 version. Everything appeared to go smoothly but as I found out this morning something just isn’t right and I am considering either reverting to an earlier version or going back to my trusty Brewpi Arduino version.
With the technical problems I was having with the Herms my mind wasn’t focussed on the brewing, so I had over chilled the wort with my flatplate chiller, not a problem just leave it overnight on beer constant set to 21˚C and then work out a profile for the Safale S-04 yeast in the morning. 21˚C is towards the top end of the recommended temperature range but acceptable, when I looked I was shocked to see the beer was just over 22˚C.. Nearly in Panic mode. I set the photon (the heart of the new Brewpi spark ) back to factory settings and re assigned all the devices but to no avail it’s still intent on boiling my brew!
I am just about ready to swap back to the Arduino version of the Brewpi. I am loosing faith in the Spark version of the controller, it just doesn’t do it for me. The old version had a readable display and you could easily control it using the knob and set its mode with wet hands, finish the clean up of the Brew Shed then go and set the beer profile up once back in the comfort of the lounge. The spark version just is’t as readable and you need a smart device to change the settings, smart devices don’t work very well with wet hands…..in my eyes the move to the spark/particle lost usability in favour of promised multi chamber support which so far has turned out to be vapourware as Elco has stuggled to maintain the demand from his store and put in Development time… you can’t currently even set the Brewpi to beer/fridge constant using the touch screen, the only saving feature so far has been the HERMS configuration but I’m finding that unwieldy as I use 2 different mash tuns so have to swap between two different beer sensors and have to set two different beer-fridge KP settings and so have to re configure instead of being able to select a different profiles for the mash tuns.
Personally I think Elco has made a mistake and royally f@*ked up ! (yep I know it’s easy to say with hind sight ..) considering the amount of posts on the forum concerning the arduino there was room for two products. The arduino version of the BrewPi had a large user base and had attained a mature state and was very usable and stable as a single chamber fermentation controller for the home brewer, then a lot of code refactoring and object orientation went on to try and go multi-chamber and started the transition to an ARM based device with more resources- the SPARK controller (as it was called then) and it became less stable .. It would have been nice to freeze development of the arduino and still sell it and hire someone to look after the store and any support issues and Elco concentrate on the dev work for the new semi professionally orientated multi chamber system that the micro and nano brewers were shouting for…
Elco if you read this, sorry .. it has turned into a bit of a rant.. your original idea for the BREWPI was fantastic and I have used it with great success and given me pleasure in the process I do truly hope things get turned around and become successful for you..
as always to finish up here’s the Treacle Porter recipe
Hi Richard,
I’m sorry to hear that you have issues with the Spark.
The Arduino version had many conditions for enabling the actuators (like heat when the fridge temp is too low, but unless the beer temp is already higher). This made it less sensitive to wrong configuration, it could work quite well with the actuators swapped even.
The Spark version has fairer control algorithms which less arbitrary conditions that can interfere, but it does need a good configuration. With proper configuration, it does outperform the Arduino version.
In your case, I see that your fridge setpoint is very high and the fridge temp can just not reach it. You have integrator windup in the period where the fridge setpoint is below the limit, but still not reaching it.
What is happening in your chart:
– Your beer to fridge Kp is way too low. This causes the integrator to do the work that the proportional part should do, causing unnecessary windup. Increase beer-to-fridge Kp to for example 10. This will also cause the setpoint of the fridge to decrease much quicker. You can see it like this: with a very low Kp, the integrator is doing all the work. The integrator is very slow to respond (by design).
– You should also decrease the beer to fridge max difference, so your fridge setpoint clips to a lower value. As long as it is clipped to max, the integrator is held at zero. Clipping it to a lower value will not do you any harm, as you are not reaching the setpoint anyway.
I hope this helps. You definitely should be using 0.4.4, there are stability and integrator anti-windup improvements in it that you really want to have.
If you have any questions on the best configuration for your setup, please just write me an e-mail. The issues you have are easily fixed with a change in the settings. No need to rant about it 😉
Elco