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Arduino Keg Sensor for Level, Temperature, and Pressure with Display

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UncleD

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Any updates?
Yes! I've got a handful of these in the hands of homebrewers that are testing as we speak. I am putting together documentation and integration support as well so this will be something that folks of any technical level can set up, and use in various different applications.

I appreciate the follow up and the patience. I want to make sure all the "bugs" are worked out before rolling it out to you guys! I'm hoping to have something solid in the next few weeks!

Cheers!
 

LBussy

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Not sure if Derrick wants us to post pics, since there may be changes from what we have in our hands. That said I can tell you that this is very well thought out.

I find it interesting, as a guy who tries to support Homebrew software, the way he's approached this. A lot of our projects have a common theme even if it's a completely different product. I think that comes from us having used the other Homebrew products. Derrick has come at this with a clean slate and, well, it's just cool how he's done things so uniquely.

I'm not sure he was ready for me to be as honest as I was in some places, but he took it like a champ and is addressing those areas. Also, keep in mind this is in "productive use" right now on his stuff, so what I mentioned to him qualifies more as edge case stuff and is a product of what I've seen some of you break in the past. ;)
 

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To @Dexlor, load sensors have been tried, but there are intrinsic issues - like putting devices at the bottom of a cold cabinet that might get swampy at times (which pretty much kills any notion of using an actual digital scale) along with load cell drift innate to the tech...

Cheers!
I have a Wi-Fi load cell hookup in my keezer that works fine. I put my load cell unit on a platform that is itself suspended off the keezer floor, sitting on 4 screw legs. Thus, it shouldn't get wet.
Drift is very minimal so far, less than a pints' worth. Plus, perfection is the enemy of good. To me, worrying about absolute exactitude in volume left seems overly type-A.

The advantage of a load cell is that it can also be used as a proxy for fermentation gravity. I ferment in kegs, so when the weight of the keg stops decreasing, via CO2 being released, fermentation is done!
 
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UncleD

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So we'll never see a picture of the sensor side?
There will be plenty of pictures and documentation on this. I am still working on getting it put together and changes are being made based on user-feedback. The last thing I want is a bunch of people repeating the mistakes I've made when building this ;)

Not sure if Derrick wants us to post pics, since there may be changes from what we have in our hands. That said I can tell you that this is very well thought out.

I find it interesting, as a guy who tries to support Homebrew software, the way he's approached this. A lot of our projects have a common theme even if it's a completely different product. I think that comes from us having used the other Homebrew products. Derrick has come at this with a clean slate and, well, it's just cool how he's done things so uniquely.

I'm not sure he was ready for me to be as honest as I was in some places, but he took it like a champ and is addressing those areas. Also, keep in mind this is in "productive use" right now on his stuff, so what I mentioned to him qualifies more as edge case stuff and is a product of what I've seen some of you break in the past. ;)
Thanks for posting pics @LBussy, and thanks for your feedback!

I have a Wi-Fi load cell hookup in my keezer that works fine. I put my load cell unit on a platform that is itself suspended off the keezer floor, sitting on 4 screw legs. Thus, it shouldn't get wet.
Drift is very minimal so far, less than a pints' worth. Plus, perfection is the enemy of good. To me, worrying about absolute exactitude in volume left seems overly type-A.

The advantage of a load cell is that it can also be used as a proxy for fermentation gravity. I ferment in kegs, so when the weight of the keg stops decreasing, via CO2 being released, fermentation is done!
Load cells are another great measurement methodology. I had thought about doing something like this instead of the lid, but I did like the pressure capability of the lid. Even bought some load cells to play with...

I'd be really interested in the success you had with measuring a change in gravity. It seems like the accuracy of the load cell would have to be pretty high to be able to measure the change in specific gravity of a known volume. I experimented quite a bit a while back with differential pressure of submerged transducers at a known height differential and those sensors had to be extremely accurate. Not to derail the conversation too much... 😂
 

doug293cz

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...

Load cells are another great measurement methodology. I had thought about doing something like this instead of the lid, but I did like the pressure capability of the lid. Even bought some load cells to play with...

I'd be really interested in the success you had with measuring a change in gravity. It seems like the accuracy of the load cell would have to be pretty high to be able to measure the change in specific gravity of a known volume. I experimented quite a bit a while back with differential pressure of submerged transducers at a known height differential and those sensors had to be extremely accurate. Not to derail the conversation too much... 😂
CO2 density at STP is 1.977 g/L. A 5 gal fermentation of a medium gravity wort results in 400 - 500 L (@ STP) of CO2 being generated, so weight loss of the fermenter would be in the range 791 - 989 g ( 1.74 - 2.18 lb.)

Brew on :mug:
 

doug293cz

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Wait... what? You saying that 5 gals of fermenting liquid loses about 2 lbs worth of mass??
Yes, although I didn't correct for the CO2 that remains in solution, which would be about 15 L or a little over 1 oz.

Brew on :mug:
 

day_trippr

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The mass loss actually doesn't surprise me - there's a hella flow of CO2 roaring through two ball lock kegs being fed by 11 gallons of wort in the throes of fermentation and that's gonna keep chugging for 2-3 more days.

Has to come from somewhere :)

Cheers!
 

doug293cz

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We can do the weight loss math another way. Assume 5 gal of wort at an OG of 1.050, and FG of 1.010, and that there is insignificant volume change during fermentation. The density of water at 68°F (20°C) is 8.33 lb/gal. Thus the weight loss during fermentation is:
Weight Loss = 8.33 lb/gal * 5 gal * (1.050 - 1.010) = 8.33 * 5 * 0.040 = 1.66 lb​

Brew on :mug:
 

Gruel

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Here's a couple of pics:

View attachment 704693 View attachment 704694

And no, you can't see much. Thats the point. :) It's a solution, not a box of parts. A well thought-out solution. All I had to do was plug it in and attach it to my network.
I had seen the picture with the cover before. I am interested in seeing the parts below the cover. But thank you for your effort.
 
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