Monitoring spunding pressure through BrewPi/Fermentrack

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MacDee

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I've set up a legacy Arduino Uno BrewPi/Fermentrack system that I hope to eventually hookup to a jacketed conical. I also plan on adding a Tilt. I would like to add a head pressure sensor so that I could more accurately determine when to start spunding regardless of fermentation speed. I've searched the various threads but have yet to find anything on measuring/monitoring head pressure.

I've found some DFrobots.com Arduino projects regarding pressure but it would be nice to find a project for BrewPi/Fermentrack.

Anyone?
 
I don't recall ever seeing head pressure sensors being addressed by BrewPi or Fermentrack, so that's new ground to break.
But Fermentrack at least can plot your Tilt so you can watch SG, while it appears Elco is uninterested in Tilt integration at this time, and I haven't found anyone getting actual Tilt data to show up in their BrewPi plots...

Cheers!
 
Do you think I could add an arduino uno output signal for pressure to Fermentrack?

There is no existing support in Fermentrack for something like this, so if your question is whether or not this could be done without building it yourself, then the answer is - unfortunately - no.

If you are interested in building support into Fermentrack, however, then yes - this is something that could be done.
 
I was thinking that if a pressure signal was a one wire digital signal just like the one wire DS18B20 temperature probes wouldn't the brewpi just read it like another temperature sensor? The problem then would be scaling so it appeared on the same trend. I read here that a ratiometric pressure sensor could be paired with a chip like the DS2438 and give that one wire digital signal.
Or would an analog voltage be easier to incorporate?
Alas I'm not a programmer I just cut paste code until stuff works and with this I wouldn't even know what files to look at. I also don't imagine there is sufficient critical mass of brewers doing spunding to drive something like this pressure trending forward.
But I had to ask since there is a lot of amazingly inventive people bringing out great stuff for us brewers.
 
I've done that on BrewPiLess, a BrewPi variance.

Not only monitoring, I also want to control it.

https://github.com/vitotai/BrewPiLess/wiki/Pressure-Transducer-and-Pressure-Transducer-control

I use my spending valve to test and "calibrate". My pressure transducer is 0-80psi/0.5v-4.5v output, which is supposed to output 2.5v at 40psi. So I just connect the signal line directly to A0 without an additional resistor.
The error of reading was around 0.5, if I red the gauge right. The reason I have not put it into real usage is that I found it's difficult to have air tight between the threaded connection. The pressure dropped from 25 to 10psi in 40 minutes during the test.
 

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There is no existing support in Fermentrack for something like this, so if your question is whether or not this could be done without building it yourself, then the answer is - unfortunately - no.

If you are interested in building support into Fermentrack, however, then yes - this is something that could be done.
Does the One Wire Dallas directory used for the DS18B20 temperature sensors also support voltage readings from a one wire DS2438?
 
I've done that on BrewPiLess, a BrewPi variance.

Not only monitoring, I also want to control it.

https://github.com/vitotai/BrewPiLess/wiki/Pressure-Transducer-and-Pressure-Transducer-control

I use my spending valve to test and "calibrate". My pressure transducer is 0-80psi/0.5v-4.5v output, which is supposed to output 2.5v at 40psi. So I just connect the signal line directly to A0 without an additional resistor.
The error of reading was around 0.5, if I red the gauge right. The reason I have not put it into real usage is that I found it's difficult to have air tight between the threaded connection. The pressure dropped from 25 to 10psi in 40 minutes during the test.

Are you able to log the pressure on the Brewpi graph along with the temperatures?

Right now I'm working on my "feed & bleed" fermentor jacket glycol recirc system with a RPi and Arduino Uno running BrewPi/Fermentrak but I got in some Thorrak's pcb boards and components for ESP8266 BPL builds and want to add pressure tracking.
 
Are you able to log the pressure on the Brewpi graph along with the temperatures?

Right now I'm working on my "feed & bleed" fermentor jacket glycol recirc system with a RPi and Arduino Uno running BrewPi/Fermentrak but I got in some Thorrak's pcb boards and components for ESP8266 BPL builds and want to add pressure tracking.

The charting library seems to support only TWO set of data, and I already use the other for gravity. So, NO. I can't display it on the chart.
 
I've been exploring hooking my 5v 30 psi transducer as a ratiometric to a ds2438 circuit to input as a Dallas one wire signal along with my ds18s20s. I'm in way over my head but I'll post what happens.
 
That’s.... uh... do you have a BoM? That sounds kind of neat.
So far I've bought a couple pcb boards from a design for a one wire barometer. Parts list here http://www.davidbray.org/onewire/baro20PartsCal.html
I was planing on substituting a pressure transducer in place of the MPX4115. But then I was reading on the site how hard it is to solder in the DS2438 so now I'm thinking of get these in without the HI4030s. http://taaralabs.eu/1-wire-humidity-temperature-sensor/
There was a maxim DS2438EVKIT+ but I thought I could use but I can't find them available.
 
There is no existing support in Fermentrack for something like this, so if your question is whether or not this could be done without building it yourself, then the answer is - unfortunately - no.

If you are interested in building support into Fermentrack, however, then yes - this is something that could be done.

Could this dynaBus.h be inserted into the firmware to detect a DS2438 that was on the same onewire bus and substituted for say the room temperature or an added readout?

I hooked one into the same bus on the ESP8266 but it is essentially ignored on the Fermentrack device list. I used the parts in my previous post
 
Could this dynaBus.h be inserted into the firmware to detect a DS2438 that was on the same onewire bus and substituted for say the room temperature or an added readout?

I hooked one into the same bus on the ESP8266 but it is essentially ignored on the Fermentrack device list. I used the parts in my previous post

I’d imagine that the standard Arduino OneWire library would be just fine here - I’m not clear what dynaBus brings to the table that OneWire doesn’t. That said, what you describe is expected. The BrewPi firmware doesn't have support built in for the DS2438 so the device is essentially ignored.

There's not a limit on the number of devices that can be reported, so there'd be no need/benefit to replacing a DS18b20 temperature sensor with a DS2438 as opposed to just adding it. That said, not all onewire devices act the same, so doing what you describe would require that code be added specifically targeting the DS2438.
 
I’d imagine that the standard Arduino OneWire library would be just fine here - I’m not clear what dynaBus brings to the table that OneWire doesn’t. That said, what you describe is expected. The BrewPi firmware doesn't have support built in for the DS2438 so the device is essentially ignored.

There's not a limit on the number of devices that can be reported, so there'd be no need/benefit to replacing a DS18b20 temperature sensor with a DS2438 as opposed to just adding it. That said, not all onewire devices act the same, so doing what you describe would require that code be added specifically targeting the DS2438.
I thought the dynabus had the code and library needed to merge the DS2438 with the DS18b20s.
 
I thought the dynabus had the code and library needed to merge the DS2438 with the DS18b20s.
I’m not sure what exactly that code does TBQH. It appears to be that guy’s wrapper around the OneWire library to make reading both sensor types easier. That said, the BrewPi firmware has its own wrapper into which code to handle the DS2438 would need to be integrated.
 
One cannot "merge" disparate functionalities. The 2438 does not look like an 18b20.
That little "library" just extracted some onewire library bits to make talking to the 2438 and 18b20 a little easier, I guess.
The author notes you still have to load the original onewire library...

Cheers!
 
That’s.... uh... do you have a BoM? That sounds kind of neat.
What are the criteria for the "Manual Sensor" you now have on Fermentrack? I've just created a Server with WiFi on a D1 Mini that allows me to plot Spunding pressure. But it would really be useful if I could add that pressure signal or even a voltage to Fermentrack as I have that setup in my brewery controlling 3 fermenters with Remot3.io so I can check up remotely. Right now that Manual Sensor only has provisions for Temperature and Gravity

I could buy another device on the Remote3 $$ account i guess and have it reside on the D1 mini where I have that server but on the RPi3/Fementrack would be better.

I'm using a 5v transducer thru a leveller circuit to the 3.3v A0 port on a D1 mini right now but I'm still working on using the DS2438 one-wire. I'm getting closer.
 
That’s.... uh... do you have a BoM? That sounds kind of neat.
Progress!

I replaced the HIH humidity sensor on a board from TaaraLabs with a 5v pressure transducer and levelled the one wire signal down to 3.3v with a 2n7000 circuit. Once I found the right HEX address and family code,26, for the DS 2438 I was able to get the D1 Mini to spit out pressures. So it would be really great if I could get Fermentrack to take that in and record a few of those pressures as a separate controller instead of temps and sp.gr.. But if not I'll use the webserver I was able to set up on the ESP8266 D1 mini from this RandomNerds page. I should be able to add another IP service to my Remote3 device account to see that output remotely so I can watch my spunding pressures.

Meanwhile I'm pulling up all the points in the brewpiless/ferementrack codes and header files to see where I would need to use the DS2438 onewire signal instead of the DS18b20 onewire signal.

Simply walking into Mordor!
 
......... That said, the BrewPi firmware has its own wrapper into which code to handle the DS2438 would need to be integrated.

Since I've now got a webserver working with a DS2438 monitoring and plotting pressure I'm now looking at running that webserver and Fermentrack off the same Raspberry simultaneously.

Does any one know if there would be a problem of setting that pressure monitoring webserver at port:90 say. Would that mess up Fermentrack when it needs to detect other new ESP8266 mini's when I'm setting them up?

I haven't given up on modifying the Brewpi wrapper to handle the DS2438 but for now I figure this will allow me to remotely monitor pressure through Remot3 by looking at that new port.
 
Since I've now got a webserver working with a DS2438 monitoring and plotting pressure I'm now looking at running that webserver and Fermentrack off the same Raspberry simultaneously.

Does any one know if there would be a problem of setting that pressure monitoring webserver at port:90 say. Would that mess up Fermentrack when it needs to detect other new ESP8266 mini's when I'm setting them up?

I haven't given up on modifying the Brewpi wrapper to handle the DS2438 but for now I figure this will allow me to remotely monitor pressure through Remot3 by looking at that new port.

Short answer: No issue whatsoever.

Longer answer: The way that Fermentrack detects new devices on your network is by using mDNS and searching for specific device types. Adding new devices to your network (or new response types) wouldn't impact this at all - the only thing that would cause this to fail is if you changed your router to block mDNS requests from being responded to. Adding a new service to your Pi shouldn't create any issues whatsoever.
 
@MacDee you make any progress on this? I was thinking of tackling something similar to this as my next brewery project. I don't actually care about plotting the data as much as I do closed-loop control for spunding.
 
Yes. I was able to set it up. It doesn't report to Fermentrack but rather a web server That I found on Randomnerdutorials.com. It gives an approximate pressure +/- 0.5 psi and I have it plot about 40 points on 15 min intervals. I then use Remot3.it to call my rpi3 up with VNC and look at the plot. I only have one 5v 30 psia sensor hooked up to a ds2438 but because it is a "one wire" protocol I could hook up more. I don't control with it yet but I plan to eventually. I was hoping I could could sub in the DS2438 signal instead of 18b20s into Fermentrack but I haven't figured that out yet.
 
Pressure is building to be able to monitor pressure. I'm working one project with a pro-brewer who wants pressure monitoring on a small brewery and now that I'm pressure fermenting my lagers, I'd like to track it as well.
I'd love to see this all on one solution - like Fermentrack. But if that isn't possible, I might try building this on ESPhome using the Honeywell ABP sensors and bringing it all into Home Assistant.
 
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