remote pressure monitoring

[dtashmore547]

this is my first post and I would like to give back a little to this forum for all the help it has given me.
does anyone else have the same problem as I had? having gone into pressure fermentation and finding it very advantageous I was concerned with monitoring my pressure, my fermentation chamber is in my brew shed at the bottom of the garden and proved awkward for monitoring the pressure from my kegland spunding valve, my solution was to put the information on my wifi via a esp8266 module. if anyone with sufficient soldering and programming (Arduino) skills would like the info please respond via this thread and I can post the details.
components used
I used an esp8266 esp-07 with external antenna plus ceramic antenna
for the distance required but others will suffice as it only requires 1 analog I/p and 1 digital output for a meter (pwm)
1 x 3135 20v digital meter ( changed solder points on back to give 1 decimal place)
1 x XGZP6847200KPG 200 kpg pressure sensor module (29psi)
1 x usb to serial module to program the esp module
1 x 80-250v to 5v 700mA supply
1 x 3cm by 7cm pcb prototype board
2 x project box 7cm W by 13cm L by 4cm H
4 x 10k resistors
1 x 5k6 resistor
1x 1k6 resistor
1x 1k resistor
1 x 4 pin single row 0.1in header to connect with the usb to serial module
2 x 0.1uF ceramic capacitor
so the cost is fairly minimal

 

[LBussy]

I'd like to see more about it - can you share it here in case someone else would like to see it?

 

[dtashmore547]

just wish you had replied a week ago, just had a disaster with my computer, lost my home partition and with it all my programs,stupidly not backed up for a few months, will have to get my program re-written but will take a few weeks as there are a couple of other items to recover first. I will post this project once I have it back. please excuse my error and keep an eye open for the update

 

[LBussy]

Oh no!

May I suggest something like GitHub in the future? Too many folks think GitHub is for "pros" and don't make use of it. The truth is, there's a lot of REALLY crappy code on GitHub. Never be embarrassed about sharing - someone else may jump in and want to help out and contribute making it even better.

I think the code to do this would be reasonably straightforward so I'd not get too twisted around the axle on that one. I'm curious about your physical implementation and potentially a schematic (or a pic of the hook-ups.)

Did you use the Analog meter as a pseudo-pressure gauge?

 

[dtashmore547]

hi Lee
you're spot on, never considered github, the code is only an adaption of an ajax server example from the net, when I have time I will duplicate it and post. for the time being I will put a circuit diagram together and a couple of photos and put them on this post.

 

[dtashmore547]

these are photos of the setup in situ.
the feed ours from a spunding valve into a pressure 200kpg (29Psi) transducer which gives out 0.5 to 4.5 volts, this is then reduced to 0.1 to 0.9 volts for the ESP8266 module.
the output of the ESP module is 0 to 5 volts via pwm and a filter the system is supplied by a 220v to 400mA@5volt SMPS.
I utilised an ESP unit that requires an aerial due to the distance between my home and shed +- 25 meters.
the meter display is 5135 20 volt meter the meter has solder points on the back to change the regional point, this should be changed to show 1 decimal place. the input should be 2.9 volts at 4.5 volts from the pressure sensor. I live at 1500mts altitude, this changed the zero value so altitude should be factored into the output calibration of the ESP device.
the system was mounted on 0.1 inch prototype board.
I hope to upload a circuit diagram soon.

 

[dtashmore547]

data sheet for the pressure sensor

 

[dtashmore547]

this is the circuit diagram and ESP8266 data sheet

 

[dtashmore547]

the pressure sensor is driven by the 5/16 inch gauge output of the spunding valve, the sensors come with a length of clear plastic pipe, to adapt from 5/16 to the small pressure sensor pipe I used 75mm of 1.2mm refrigeration copper capillary pipe and soldered it to 5/16 copper pipe.
attached is a screenshot of the web page

 

[LBussy]

Got ya! I like the setup - and I think I recognize the temperature control there underneath?

 

[dtashmore547]

hi Lee
the temperature controller is a small part of my fermentation cupboard, just there to prevent my heater (3 power resistors on a heatsink) from getting too hot the the main controller is of my own making and uses a pic16f866 with an mcp9808 temperature module to control the heater and a homemade refrigeration unit.

 

[LBussy]

uses a pic16f866 with an mcp9808 temperature module

I was talking about what looks like a XH-W1219 down below.

I greatly prefer monitoring and reporting pressure to some of the setups I've seen where people want to control it with a microcontroller. While you can get into pretty advanced pressure profiles to optimize ester production in some beers, I hate to think what would happen if the controller decided to crash or flake out. Such a setup would require a sounding valve on top of the solenoid to act as a fail-safe.

 

[dtashmore547]

my setup is just a very simple remote monitoring of the spunding pressure so I don't need to run to my brew shed all the time, just a quick check to see if all is well.
it is a w1219 controller, it is tied in with my heater to prevent overheat conditions, wouldn't want smoke and flames in a wooden shed, it simply turns off the heater when it reaches 50 sets it back on when it drops to 49.

 

[LBussy]

Paraphrased: Simple is smooth, smooth is fast.

 

[pocketmon]

Is your pressure reading stable?
I've tried ADC of ESP8266 for pressure reading in my BrewPiLess project. It's very unstable.
I checked the document of ESP8266, which states that ADC is used only for WiFi module and will be affected by WiFi operation.
I have to use an additional ADC module, ADS1115.

 

[LBussy]

@pocketmon I was thinking about that. With the ESP32 you can use the other ADC. With the 8266 could you shut off the radio, take your reading, then turn it back on?

 

[dtashmore547]

@pocketmon I had no stability problems at all the readings are stable and consistent, have you got a good signal strength on your Wi-Fi connection? is your common connection solid? a poor common will cause noise and affect your analog, do you have a 0.1 or better ceramic capacitor across your 3.3v to common close to the pins?

 

[pocketmon]

@pocketmon I was thinking about that. With the ESP32 you can use the other ADC. With the 8266 could you shut off the radio, take your reading, then turn it back on?

I was planning to control pressure by venting, and I don't think it's feasible solution by turning off the radio.

 

[pocketmon]

@pocketmon I had no stability problems at all the readings are stable and consistent, have you got a good signal strength on your Wi-Fi connection? is your common connection solid? a poor common will cause noise and affect your analog, do you have a 0.1 or better ceramic capacitor across your 3.3v to common close to the pins?

Those might be some of the problems.
However, I believe that the radio does interference ADC according my googling, like Fluctuating ADC with stabilized source · Issue #2070 · esp8266/Arduino

 

[DuncB]

Hasn't vitotai already sorted this out for pressure monitoring and autospunding on brewpiless?

https://github.com/vitotai/BrewPiLess/wiki/Pressure-Transducer-and-Pressure-Transducer-control
I haven't taken the plunge yet with the vitotai solution and might do in the future.

For monitoring pressure remotely my solution a little less teccy works okay,

Using a clever dog camera ( usb powered wifi connected )
https://www.cleverdog.online/en/cleverdog-wifi-camera-baby-monitor-gray.html
point it at spunding valve gauge, has infra red so works inside the fridge/ ferment chamber without a light.

App allows viewing of it anywhere with internet access. Would be better if the camera had a shorter focal length.