BrewPressure - DIY pressure sensor

[Diyhomebrewers]

Hello! brewers.

My name is Daniel, I manage the website: www.diyhomebrewers.com, perhaps some of you already know me since I am Spanish but I discovered this forum because I was notified once that I was mentioned.

I made a new DIY Gadget, just to see what you think. It is a pressure sensor for isobaric fermenters.

I know it's strange that it is at the bottom and not the top, but it is intentional (it can be placed at the top without contact too) since the sensor in question allows it and I would like it to be useful for more values in the long run.

The concept of the Gadget is to be able to see the pressure data remotely, I work outside the home and I needed to see it from outside, something that a conventional pressure gauge did not allow me to do. (currently by MQTT and Brewfather)

I leave you a link with the gadget and an explanatory video.

I know it is in Spanish, sorry, it is my main language and although I can express myself in English, I think that my English is not the most suitable for writing articles with a minimum of seriousness. There are links buttons for direct translation of the article and try to give the video an extra boost with subtitles.

Ask me any questions, I will try to come here more often from time to time D). Especially if they find it interesting and it is logical to do more integrations (for me it is more than enough since I use MQTT in my current Brewblox system).

Explanation and step by step assembly: BrewPressure - Sensor de presión DIY
Explanatory video:

Greetings!

 

[CDCTx]

How precise and steady have you found these types of pressure sensors to be?

I currently use these pressure transducers from Amazon US to monitor fermenter head pressure. While it is great for my general measurement purposes, it has a lot of signal issues when going to the thousandth place (likely because I have a wire run from my fermenter control box to the transducer with other electronic things along the way.

But why would I care about measuring to the thousandth place or beyond? I recently learned about using pressure differential to measure wort density (and thus standard gravity), which is common in professional equipment.

However, at the homebrew scale of a standard 5–6-gallon batch, even using a 14-gallon conical, the pressure difference to track, for example, 1.050 to 1.010 (with 17 inches between the bottom of the conical cone to the top of the wort) is 169.44 Pa or 0.0245751943 PSI. It is likely a fool's errand to try and use pressure differential to track gravity drop at such a small scale, but I am really into coding and electronics with ESP32, so it's more of a "Can I do this?" than an expectation that it will replace the Tilts I use now

 

[Frank Nobrega]

How precise and steady have you found these types of pressure sensors to be?

I currently use these pressure transducers from Amazon US to monitor fermenter head pressure. While it is great for my general measurement purposes, it has a lot of signal issues when going to the thousandth place (likely because I have a wire run from my fermenter control box to the transducer with other electronic things along the way.

But why would I care about measuring to the thousandth place or beyond? I recently learned about using pressure differential to measure wort density (and thus standard gravity), which is common in professional equipment.

However, at the homebrew scale of a standard 5–6-gallon batch, even using a 14-gallon conical, the pressure difference to track, for example, 1.050 to 1.010 (with 17 inches between the bottom of the conical cone to the top of the wort) is 169.44 Pa or 0.0245751943 PSI. It is likely a fool's errand to try and use pressure differential to track gravity drop at such a small scale, but I am really into coding and electronics with ESP32, so it's more of a "Can I do this?" than an expectation that it will replace the Tilts I use now

I use that type of pressure sensor for my auto spunding setup. I am using it on an ESP32 Brewpiless controller and find that the pressure reported varies by about 0.2 psi when I have a constant pressure applied. Right now I am cold crashing and if I watch the pressure as being reported by Brewpiless, it is reading 9.1 psi but then dropping to 8.9 psi and then going back to 9.1 psi. I haven't tried to see if I can get it any better because for my purpose it works fine.

 

[DavidWood2115]

How precise and steady have you found these types of pressure sensors to be?

I currently use these pressure transducers from Amazon US to monitor fermenter head pressure. While it is great for my general measurement purposes, it has a lot of signal issues when going to the thousandth place (likely because I have a wire run from my fermenter control box to the transducer with other electronic things along the way.

But why would I care about measuring to the thousandth place or beyond? I recently learned about using pressure differential to measure wort density (and thus standard gravity), which is common in professional equipment.

However, at the homebrew scale of a standard 5–6-gallon batch, even using a 14-gallon conical, the pressure difference to track, for example, 1.050 to 1.010 (with 17 inches between the bottom of the conical cone to the top of the wort) is 169.44 Pa or 0.0245751943 PSI. It is likely a fool's errand to try and use pressure differential to track gravity drop at such a small scale, but I am really into coding and electronics with ESP32, so it's more of a "Can I do this?" than an expectation that it will replace the Tilts I use now

These pressure sensor’s stated accuracy is +/- 2% full scale, so for the 30psi model that is +/- 0.6psi. Reading beyond the tenth’s place will not give you any more accuracy.

You should look at the Honeywell sensors, like the hscmand015pa2a3, which has an accuracy of 0.25% full range. This one has a 15psi max, so the absolute error is +/- 0.0375 psi. That gets you down to the 100ths places. I think that’s the best you can do with (reasonably) cheap parts. Also you are going to want to find one that is rated for liquid contact, which are harder to find.