CraftBeerPI Brew Controller

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loco88 said:
Can any of you blokes take a few pics of your Pi/Relay/Probe setup for me? I've setup a BrewPi before but that wasn't using the Pi pins, plus I want to see if I have enough spare parts lying around to make one of these :D Cheers
Hey loco88 - I have some pics in this Google Drive link
Im pretty sure this is how i set mine up via a breadboard.
A Tip - don't use Fotek SSR as i could not get mine to activate direct from the GPIO pin voltage without adding in a transistor circuit to provide additional voltage. I switched to Inkbird and it worked direct from GPIO Pins as expected, so i am ditching the transistor complexity.
 
I'd like to point out that my Fotek works perfectly fine. I think you need to be careful on which ones you get, as there are some fake ones out there.
 
tumi2 said:
Hey loco88 - I have some pics in this Google Drive link
Im pretty sure this is how i set mine up via a breadboard.
A Tip - don't use Fotek SSR as i could not get mine to activate direct from the GPIO pin voltage without adding in a transistor circuit to provide additional voltage. I switched to Inkbird and it worked direct from GPIO Pins as expected, so i am ditching the transistor complexity.
That's pretty much what I'm looking for, cheers. I plan on adding a pump, so two relays but that's a good start, thanks.

Although...
ImageUploadedByAussie Home Brewer1471491278.915984.jpg
 
Just so you know, those are both counterfeit units
But there are reports of fake ones doing the job just fine, but the odd one will be out of spec due to lack of QC
 
sp0rk said:
Just so you know, those are both counterfeit units
But there are reports of fake ones doing the job just fine, but the odd one will be out of spec due to lack of QC
Any easy way of telling fake from real? Save me a google seeing as you know what I'm actually using them for!
 
http://www.ul.com/newsroom/publicnotices/ul-warns-of-solid-state-relay-with-counterfeit-ul-recognition-mark-release-13pn-52/
Basically, the bottom right corner of the label should have a small bit missing (on the real ones)
Also they should say "Made in Taiwan" "Rated: 10A Max"
Looks like they've started adding the Taiwan claim to the counterfeits

Most things I've read on the dodgy Foteks say they work fine, but they're under-rated
Most of the 20A ones have 12A triacs, so if you're trying to switch a 15A circuit, she'll go boom
You having 10A SSRs, I'd possibly be a little careful with them
Using higher rated SSRs isn't a problem, you're safe to use 20A or 40A SSRs for a 10A circuit
 
Dave_022 said:
SSR's are fairly resilient that is why they are preferred over Electro-mechanical Relays (EMRs) these days. The mean time before failure of an EMR is about 100K where as an SSR will operate between 50-500 million times before failure. Implementation of PID logic for temperature is generally as follows.

Take the total output power of a system (say 2400W)
Take the error; which is the difference between the setpoint and measured temp.

Then the error is used to determine the proportional, integral and derivative which basically try and ramp temperature up as fast as possible without overshooting or creating a 'ripple effect' by measuring the changes to error over time.

This gives a % of power required at any given (preferably regular) interval at which the calculation is performed.

If the system is analog then you can simply set the power i.e 1200W for 50% etc.

However to use a digital system which only does on and off you select a window (5 seconds for example) and set a duty cycle from this; so for your 1 second on 4 seconds off it is working at 20%.

What you should see is it on all the time at the beginning and as you approach set temp it to spend more time off than on.

Given the above failure times and the use in this application i wouldn't worry to much about the SSR and the heating element won't know the difference between being operated like this and having a lower current passing through it because it is just a big resistor.

In comparison overshoot just realises that the element will still be hot when the power has gone and therefore it will continue to rise until it reaches equilibrium; so we take a punt at what the residual temperature rise will be. Obviously you can easily measure this by manually heating water, turning it off and measuring overshoot.

PID is a bit more complicated as you need to balance P, I and D to ensure that actually temp is reached; and in a timely manner and that it doesn't overshoot.... which is short, is a sod.

So why PID? When set properly the temperature will rise evenly without overshoot and then stay within about 0.1 degree C.

However, PID systems usually control systems where the setpoint changes and you don't want too much overshoot i.e. a missile guidance system where the target moves and you don't want it flying too far left then too far right etc etc.

Water heating on the other hand is a simple system so it may be considered overkill for this application; a bang-bang temperature control should be able to keep you within 1 degree easliy and probably better.

The choice is yours of course; in the past I have gone for PID because I spent ages perfecting the algorithm for another application on Arduino.....

On the other hand, I also like to drink beer so spending ages calibrating a system may fall further down on my priority list...
Thanks for that explanation. I am going to give PID another go next brew but this time take close notice of how it works, timings and switching.
 
Has anyone upgraded to Dev2.2 of Craftbeerpi?. There seem to be some people using it and i can see on Git Hub that Manuel has been a busy developer and made lots of good changes recently.... all power to him i say :beerbang: :beerbang: .

I would like to upgrade but am not sure how i go from 2.1 to 2.2.

Do i just rename the current craftbeerpi folder and then run a git clone https://github.com/manuel83/craftbeerpi/tree/dev2.2 then run the install script to get a new installation of Dev2.2 or is there an upgrade path?
 
Hi

Version 2.2 is under heavy development. I updated all the python libs to the latest version and now I'm fixing issues.
I don't recommend to you version for brewing but any help for bug fixing is appreciated.

You can clone this version by using the following command:

git clone -b dev2.2 https://github.com/Manuel83/craftbeerpi

Cheers,
Manuel
 
Thanks Manuel. Im happy to clone and install dev2.2 into a different directory on the RPI to help with bug testing.

If i do will 2.1 still work?
 
CBP2.2 is under heavy development. I do a lot of changed. Last week I updated all the python libs to the lastest versions. This was a major change.
Unfortunately these libs are not compatible to the libs used in version 2.1. To run both versions on one RPi I recommend to use virtualenv.

http://docs.python-guide.org/en/latest/dev/virtualenvs/
 
Manuel said:
CBP2.2 is under heavy development. I do a lot of changed. Last week I updated all the python libs to the lastest versions. This was a major change.
Unfortunately these libs are not compatible to the libs used in version 2.1. To run both versions on one RPi I recommend to use virtualenv.

http://docs.python-guide.org/en/latest/dev/virtualenvs/
Thanks Manuel, i have now installed dev2.2 and 2.1 does not work as you mentioned but that is fine as i do not need to brew for a while.

Dev2.2 looks really good. It is much easier to identify hardware and the way you can name and view hardware is better. I also like being able to export the temperature profiles. Looking forward to the fermentation module being available as that looks good also.

How would you like me to report bugs? Should i just add them as Issues in GitHub or do you want me to put them in this thread?
 
Please use github for reporting issues but keep in mind 2.2 is still under development.
 
anyone tried PiZero? Does it work? Maybe dietpi.com would be nice idea, even for normal RPi 2/3

BTW you can check my github for some PCB's for CraftbeerPI similar to ArdBir's ones.

https://github.com/terragady
 
I tried setup on dietpi as it is quite minimal; GPIO for 1-wire doesn't work out of the box to read sensors so it is a pain. Settled on Raspian Lite in the end as the fastest to setup.
 
Dave_022 said:
I tried setup on dietpi as it is quite minimal; GPIO for 1-wire doesn't work out of the box to read sensors so it is a pain. Settled on Raspian Lite in the end as the fastest to setup.
Do you use Raspberry Pi Zero?
 
No, I was using model 2, I dont have a zero was thinkng of using a 3 though, just torn between other projects i have that may require the extra power as this seems quite lightweight. However i want to use the most stable setup as, while i can keep an eye on a kettle during brew day, an interruption to fermentation over a few days would be a pain!
 
can anyone help me with the commands to run an upgrade over version 2.2. I installed v2.2 about 1 month ago and wanted to upgrade to any recent changes Manuel has made in the last month.
 
Can't you just install it from scratch again? 2.2 doesnt not meant to be for brewing yet, just for development from what he says.
 
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