arduino Keezer-meter project

[krashkropp]

Hello all this is my first post. Recently I have been working on a circuit board and code for my kezzer to display how much beer is left in each keg, how much co2 is left, and the temperature inside the kezzer. More recently I have added a fan, second temp sensor and second system for a backup co2 tank. I was hoping to get some feedback of the features that I have added so far. I Know others have done similar systems but not in the way I was wanting mine. Most of what I can find all use a flow meter and will measure how much beer has poured through the tap. I wanted a system that would let me know how much was in the keg regardless of how much I started with without calibration every keg change. The CO2 tank would also be useful information. My system uses scales to measure the amount of beer or Co2 left, subtracts the weight of the keg or tank and displays it on a LCD screen in percentages. This gives me about ½ beer accuracy. I have made a calibration sequence to measure the weight of an empty keg and the weight of 5gal liquid + keg. The name of the beer and alcohol content are also visible on the LCD but are manually input. The temperature is displayed in celsius and fahrenheit and the fan has 10 increments adjustability for speed to circulate air in the kezzer. I have finished a prototype minus the addition of the fan. Like I said I am looking for advice and input on features that should be added, changed, or improved. Please let me know what you think.

 

[helterscelter]

interesting. can you detail some about what sort of scales you use? do they suffer from drift if left under load for extended periods of time? Drift is the biggest issue I've seen with folks discussing using weight as the measurement mechanism. it's also important to take into account the final gravity of the beer/liquid in the keg as that affects the weight when full.

 

[estricklin]

Would love to hear more about what type of scales your using also.

Very nice work. I love that it's a bit simpler than most other similar systems. I personally only have 2 kegs so I would like to build something like this. For me I would add a simple circuit to switch a PC fan off and on every 30-60 seconds to keep air moving, without loosing any efficiency, (my door leaks a little).

I think it would also be great if there was a way to save a list of beers and ABV percentages, and select from them so that the arduino doeosn't have to be connected to a computer and code updated each time the kegs are changed.

I've only done a few basic projects with the Arduino so I'm still learning with it, but having lots of fun too! Thanks again for posting this and I'm looking forward to any more information, or updates.

 

[krashkropp]

The scales I am using are half-bridge 50kg load cells (4 load cells per keg) and cost about $5 per set on ebay. I also have some concerns about the drift and will have to post more information once I have finished a long term test. As for the beer gravity I will add a section that will allow for user input and run the calculation before it outputs the percentage left.

For me I figured it would be easy to pull of the arduino nano chip and go plug it into my computer to change the names and ABV but I agree that it would be useful to have it adjustable from the lcd. So I think a good way to fix that is to add a sub menu. Once a keg has been selected the up and down buttons will navigate through a sub menu with beer name, ABV, gravity, calibration, and return to main menu. If a sub menu item is selected that item will be adjustable before returning to the main menu.

I have added pins for a solid state relay that I will be using to now control the temperature of the kezzer. The solid state relays are cheap around $4 and can handle 40A.

Some others have had problems with the tmp36 sensor I am using on the 5v rail so I have moved it to the 3.3v and it seems to be stable. The default aref voltage on the arduino is 5v and can be set to an internal 1.1v setting this made the arduino lose the ability to read temperature above 140 degrees fahrenheit which is fine for a kezzer since we only really care about lower temps. The trade off is improved accuracy my temperature only jumps around about ½ degree fahrenheit.

The pc fan is already implemented and as long as it is a 4 wire fan like a cpu fan the speed can be controlled to a bunch of different settings it can even turn on when the temp on the board is different than the temp at the bottom of the kezzer(second remote temp sensor.)

To fully load the pcb and buy sensors I think it will be around $60. Each set of scales and amp cost about $7 so it is going to depend on how many kegs and co2 tanks one has.

Thank you for the feedback if anyone else has a good idea on something that can be added or changed please let me know I used almost all the pins on the arduino but there is still a lot that can be done on the software side. I will be working on the sub menu and relay and post more info when I have it working.

 

[krashkropp]

I have had some time to work on the sub menu and think it is done. If a keg is selected with the 3rd button on the back of the pcb it will enter a submenu with 5 options name, gravity, ABV, calibrate, and return. All are functioning and save the value to the eeprom so it can be unplugged or safe if it has a power loss. I have 15 names for beers saved at the moment but could go as high as memory allows probably around 100 max. The gravity that is set for the keg affects the displayed % value so I will probably use water when calibrating the sensors. This will also help when checking for long term drift. the ABV adjustment very easily and has a range of 0-15% in .1% increments. The calibration is the same as before but simplified to save space. The relay is now fully functional according to the set temperature via a sub menu from the temp page. I have also added a timer that will prevent the relay turning on if it has turned off within the last 2 minutes and vis versa. The time for this can be adjusted with a single integer on the main page of the code. The code for the relay also checks to see if the time has increased passed the max time and rolled back to zero. This would make a problem for the previous statement as elapsed time would be a negative value. I think I have this sorted out but I will need to leave one running for 50+ days to make sure. I have received the PCB’s I ordered from china a while back and they look good to me. The only problem is I have done too many revisions to hardware and software since I ordered them that they are all but useless. The current state of the project seems done to me and I think I will be sending off for another set of PCB’s this time with rush shipping. These should be a fully working board and I can start running tests. I have added some pics of the PCB’s and the test sensor plate for anyone who was curious.

 

[estricklin]

Really good to hear! Going to look over it with more detail when I get in from work, thanks for the update.

 

[Bigdaddyale]

mark.

 

[BrunDog]

This is awesome!

 

[day_trippr]

I suggest the range for the "anti-short-cycle time" be at least 5 minutes, and preferably 10, as I do not believe 2 minutes is sufficient recovery time for domestic compressor-driven appliances. If one of these ends up controlling a keezer, there's a high likelihood that the initial user setup will include a free-hanging chamber probe, and that's an oft-demonstrated cause of short-cycling.

I'm assuming the pic is of a sensor array for one keg. Is a "set" of load sensors and amps = 4?
If it can be an arbitrary number, you could cut the sensor array cost by 25% by using three sensors per keg.

Definitely interested in the drift issue, it seems inherent to the technology.

Cheers! (And Do Carry on! )

[edit] And wrt potential drift...if your research proves there is indeed drift, and if you can characterize it, perhaps having a single - static - reference load cell would provide a method to re-correlate the keg sensor readings...

 

[nicknerd27]

Very cool project! I would also like to do a similar project with an arduino or a Raspberry Pi.

 

[BeardedBrews]

Subbed. Just let me know when I can buy one

 

[estricklin]

Are you using an HX711 for this project? I have some old load sensors from a bathroom scale I scrapped out, I might try to find a data sheet for them and order some HX711s from Ebay.

As for the relay timer, you could always call a function that turns on a pin to "HIGH" after so many days, that would operate a transistor connecting the reset pin to ground, every 49 days or whatever. But, it sounds like you have figured out a better solution through the programming.

As for the drift, I think that as long as you calibrate everything when it's cold, it won't drift much. Even if it's off by a pint or 2, that's pretty reasonable accuracy for what most of us want something like this for. The fact that it can control the temp and a circulation fan as well are what really makes a build like this worth while in my opinion.

I have some DS18B20 temp sensors ordered, I will see how well they perform in my kegerator AND my electric brewery build. I love how more than 1 of them can be connected together using a single data wire.

Edit:

I am reading online that the tmp36 is "stable under high capacitance loads", I wonder if that means long lengths of wire can be added? The Dallas one I mentioned above, I've read horror stories online of people trying to use long lengths of wire and having lots of problems.

 

[crane]

I am reading online that the tmp36 is "stable under high capacitance loads", I wonder if that means long lengths of wire can be added? The Dallas one I mentioned above, I've read horror stories online of people trying to use long lengths of wire and having lots of problems.

As for the Dallas 1 wire sensors, there were a couple of things I had to do to get them to behave over 10+ feet of cable. First problem was to add capacitance between the 5V and ground on the sensor end of the wire to prevent brown outs. May not be necessary if your wire gauge is larger than what I used. I also have 5 sensors at the end of my wire so might not be necessary if you only have 1 sensor. Second issue was to use a stronger pull up resistor on the data line. It's been working reliably for over a year now.

 

[estricklin]

As for the Dallas 1 wire sensors, there were a couple of things I had to do to get them to behave over 10+ feet of cable. First problem was to add capacitance between the 5V and ground on the sensor end of the wire to prevent brown outs. May not be necessary if your wire gauge is larger than what I used. I also have 5 sensors at the end of my wire so might not be necessary if you only have 1 sensor. Second issue was to use a stronger pull up resistor on the data line. It's been working reliably for over a year now.

I was thinking that CAT5 cable might be the best thing to use for them, and that is what I was going to try. So that capacitor is basically like a decoupling capacitor? Just shorted between 5v and ground? No resistor needed there? Any clue as to what size resistor you used for the pullup. I am going to be using 2-3 sensors with about 10ft or so.

 

[crane]

I was thinking that CAT5 cable might be the best thing to use for them, and that is what I was going to try. So that capacitor is basically like a decoupling capacitor? Just shorted between 5v and ground? No resistor needed there? Any clue as to what size resistor you used for the pullup. I am going to be using 2-3 sensors with about 10ft or so.

Correct capacitor across 5V and ground. I think I used a 10uF ceramic cap. The pull-up resistor was something like 1K if I recall correctly.

 

[krashkropp]

day tripper- "anti-short-cycle time be at least 5 minutes, and preferably 10”
Thank you I have changed this time to 10 minutes.
estricklin- “are you using an HX711 for this project?”
Yes the original amplifiers I had planned on using (AD620) did not prove to have the best resolution. I was having issues differentiating between 2 pints. The HX711 operate on SPI bus and looked to require 2 pins per scale so I did not want to use them originally.
“DS18B20 temp sensors”
Thank You for the info I never looked into changing to a different temp sensor because the tmp36 was working well and was so cheap. These also seem to be inexpensive and the fact that I can use multiple on 1 pin gives me another pin to play with on the project.
crane- “capacitor across 5V and ground. I think I used a 10uF ceramic cap”
Thanks for the advice I have added locations for 3 caps if required.

Current status- The HX711 modules are cheap, $1 and free shipping! I did not want to use these because it would use 10 pins and I didn't have that many after adding the fan, relay, extra temp sensor, and sub menu button. After testing The HX711 I found that I can run a common input on all the modules with individual outputs so with the 6 pins that were in use can read 5 sales. With the ds18b20 temp sensor allowing multiple sensors on 1 pin I am back to 6 scales. I will be mounting the HX711 modules on the scales themselves. I think micro usb cables will be a good way to wire the scales to the PCB. A 4 pack of 6’ cables is $7 on ebay and can be easily unplugged. In the most recent PCB revision I used both pins and micro usb to connect the scales. To test the HX711 modules I used some resistors as jumpers to have the correct pin-outs. During testing the module shows resolution of about 1.5oz reliably. This should make the “drift” issue fixable is it does happen. Since the HX711 also has a 24 adc the raw output value is quite high and will require a very different setup for saving information to the eeprom.

Current features-
3 button interface
up to 3 temp sensors
fan output with PWM speed control
relay output for temperature control
6 scales for kegs and co2 tanks volume measurement
pre saved beer names
adjustable ABV
adjustable OG
calibration sequence
temperature display
temperature control

Other things that have crossed my mind are a co2 sensor to detect a hose leak. I did not add this because the sensors I found were $50+. Another option would be to measure another gas and see if its ppm drops significantly. The addition of a humidity sensor is another possible option and might help others with mold problems that I read about. An alarm would be annoying to me so I did not add one. The backlight for the lcd could be flashed on and off if anyone has a good idea on how it could be used. If anyone else has an idea on what should be added or wants to know anything about what I have done please let me know. Thanks to everyone that has helped thus far.

Problem: I just found out that the analog pins A6 and A7 do not have digital output capability. To fix this I will need to use all 3 buttons on A6 or A7 with external resistors. A0 - A5 still work for 5 scales plus 1 pin from the 3 buttons and the second pin from the buttons will be for the temp sensors.

 

[estricklin]

day tripper- "anti-short-cycle time be at least 5 minutes, and preferably 10”
Thank you I have changed this time to 10 minutes.
estricklin- “are you using an HX711 for this project?”
Yes the original amplifiers I had planned on using (AD620) did not prove to have the best resolution. I was having issues differentiating between 2 pints. The HX711 operate on SPI bus and looked to require 2 pins per scale so I did not want to use them originally.
“DS18B20 temp sensors”
Thank You for the info I never looked into changing to a different temp sensor because the tmp36 was working well and was so cheap. These also seem to be inexpensive and the fact that I can use multiple on 1 pin gives me another pin to play with on the project.
crane- “capacitor across 5V and ground. I think I used a 10uF ceramic cap”
Thanks for the advice I have added locations for 3 caps if required.

Current status- The HX711 modules are cheap, $1 and free shipping! I did not want to use these because it would use 10 pins and I didn't have that many after adding the fan, relay, extra temp sensor, and sub menu button. After testing The HX711 I found that I can run a common input on all the modules with individual outputs so with the 6 pins that were in use can read 5 sales. With the ds18b20 temp sensor allowing multiple sensors on 1 pin I am back to 6 scales. I will be mounting the HX711 modules on the scales themselves. I think micro usb cables will be a good way to wire the scales to the PCB. A 4 pack of 6’ cables is $7 on ebay and can be easily unplugged. In the most recent PCB revision I used both pins and micro usb to connect the scales. To test the HX711 modules I used some resistors as jumpers to have the correct pin-outs. During testing the module shows resolution of about 1.5oz reliably. This should make the “drift” issue fixable is it does happen. Since the HX711 also has a 24 adc the raw output value is quite high and will require a very different setup for saving information to the eeprom.

Current features-
3 button interface
up to 3 temp sensors
fan output with PWM speed control
relay output for temperature control
6 scales for kegs and co2 tanks volume measurement
pre saved beer names
adjustable ABV
adjustable OG
calibration sequence
temperature display
temperature control

Other things that have crossed my mind are a co2 sensor to detect a hose leak. I did not add this because the sensors I found were $50+. Another option would be to measure another gas and see if its ppm drops significantly. The addition of a humidity sensor is another possible option and might help others with mold problems that I read about. An alarm would be annoying to me so I did not add one. The backlight for the lcd could be flashed on and off if anyone has a good idea on how it could be used. If anyone else has an idea on what should be added or wants to know anything about what I have done please let me know. Thanks to everyone that has helped thus far.

Problem: I just found out that the analog pins A6 and A7 do not have digital output capability. To fix this I will need to use all 3 buttons on A6 or A7 with external resistors. A0 - A5 still work for 5 scales plus 1 pin from the 3 buttons and the second pin from the buttons will be for the temp sensors.

What type of LCD are you using? The I2C ones HAVE to use A4 and A5. If I understand, the HX711s, each one can utilize 3 load sensors, or is it just easier to put one on each "scale"? Does it matter which pins the HX711 connect to? If it has to use those analog pins, I may need to order some different LCDs, or desolder the I2C converter.

Thanks to you! I am so going to build one of these, just trying to figure out the parts I'm going to need, also I need to knock this electric brewery build out too. Sigh...so much to do.

Edit:

Ok I worked all night so have been up too long, I read your post again. I did some research on the HX711s and I see how they be connected with 2 wires for each sensors, but I haven't dug deep enough to understand using the common input. But ya, if it had to be 2 pins/sensor that would be way too many pins, would require using a Arduino Mega probably for a project like this. I did see that Adafruit has some sort of "combinator" board, so it shouldn't be too hard. I am going to order some HX711s and load sensors.....after I sleep.

 

[BeardedBrews]

The backlight for the lcd could be flashed on and off if anyone has a good idea on how it could be used. If anyone else has an idea on what should be added or wants to know anything about what I have done please let me know.

LCD might flash for a low keg, low co2, large difference between temperature probes (top/bottom of chamber), out of tolerance temperature, excessive temperature cycling (# on/off per hour), gradual drift in a scale (lost calibration or a leaking beer line).

As far as additional modules, is there a convenient way to monitor power draw (kwh / amps / watts) of the kegerator during operation? Humidity would be a good addition to spot problems with insulation and seals. You could also consider a secondary relay output for heat, for our friends from the North.

 

[krashkropp]

estricklin- What type of LCD are you using? The I2C ones HAVE to use A4 and A5.
I will be using a 16x2 lcd but with no I2c module. I went this way because mounting was a bit trickier not that it couldn't be done later. I would recommend getting a new lcd for sub $2 or de solder the i2c module.
If I understand, the HX711s, each one can utilize 3 load sensors
I only looked into this slightly but found that people were having issues so I took the easy route by using 1 on each scale. I also had concerns with the resolution changing since the 3 spots for load cells are all different gains. That and they are only $1.

I would post a parts list but they change every time i find a problem. I’m glad to see someone else will get some use out of this project. I also am doing the electric brewing project and just ran tests on a 10 gal pot. I am using an arduino also on that and can start a new thread if you or others are interested.

So the HX711 need 25, 26, or 27 pulses to sck to tell the chip to start sending the 24 bit value from the scale. So what I am doing is sending that command to all the Hx711’s at the same time and only reading 1 at a time then sensing the pulses again reading another and so on.

beardedbrews- LCD might flash for a low keg, low co2, large difference between temperature probes (top/bottom of chamber), out of tolerance temperature, excessive temperature cycling (# on/off per hour), gradual drift in a scale (lost calibration or a leaking beer line).
I agree and It may be used for all of the above as an alert an addition to text on the lcd.
As far as additional modules, is there a convenient way to monitor power draw (kwh / amps / watts) of the kegerator during operation? Humidity would be a good addition to spot problems with insulation and seals. You could also consider a secondary relay output for heat, for our friends from the North.
Good ideas! I never thought of people needing a heater. second relay output added. I have not messed with power consumption but I will look into it. I will also try to use use dht11 for basic humidity monitoring.

So I must have been drinking too much homebrew lately. I had a pin set to ground to make it easy on lcd traces. The extra pin I needed was there all along. We now have
6 scales
3 temp sensors
backlight control
3 buttons
2 relay outputs
possible humidity sensor or current meter.
here is a pic of the board it still needs some work but I think it’s almost done.

the current scale with hx711

old board revisions

and the electric brewing setup testing and all good

 

[BeardedBrews]

This is not a question directly related to the board, but rather to the programming. Is it possible to selectively couple temperature sensors to relay outputs?

Probe - Condition - Action
T1 - High - R1 On
T2 - High - R2 On

This would give some flexibility if a user didn't need to add heat. Instead it could cycle an internal fan on and off if the top of a chest freezer (serving lines and collar area) gets warmer than the bottom. This would also give the user the option of controlling a second kegerator or fermentation chamber from the same board.


[Edit]
I forgot to ask, are you controlling the electric kettle with the same controller?

 

[krashkropp]

This is not a question directly related to the board, but rather to the programming. Is it possible to selectively couple temperature sensors to relay outputs?

Probe - Condition - Action
T1 - High - R1 On
T2 - High - R2 On

This would give some flexibility if a user didn't need to add heat. Instead it could cycle an internal fan on and off if the top of a chest freezer (serving lines and collar area) gets warmer than the bottom. This would also give the user the option of controlling a second kegerator or fermentation chamber from the same board.


[Edit]
I forgot to ask, are you controlling the electric kettle with the same controller?

Yes the temp sensors can be set to control anything. I planned on having one at the top and one at the bottom and control the fan accordingly. If someone is not using the second relay the 3rd temp sensor could be used for fermentation control good idea.

I am not using the same setup for the electric kettle
1 I nedded to use a K type thermocouple and that requires a module
2 The menu to set temps and times save load hop times and temps nedded more buttons to be easy
3 cost
The setup I am using is an arduino uno and lcd keypad shield

 

[BeardedBrews]

Time to bring this thread back to life, any changes or progress on the project?

 

[krashkropp]

Yes sorry for no posts. I am taking a class for C++ computer programing that is greatly helping with making the code easy for others to use and modify. I will also have some added features. There are only a few weeks of the class left and I would like to finish the class before I rewrite the code. I am also looking at making a windows app to easily modify the code so no one will ever have to touch any code. The pics are of the most recent pcb with micro usb ports for connecting of each scale there is also an error check at the beginning of the program to see what is connected. Anything that you guys want added or changed please let me know as I am eager to complete this project as I assume some of you may be as well.

 

[krashkropp]

 

[BeardedBrews]

The idea of using a micro-usb header for the scale connection is great!

I see the six scale inputs, how are you handling the temperature inputs and relay outputs?

 

[krashkropp]

The temp ic's can be mounted on the pcb or remotely with the pre made waterproof ds18b20. the relays are made to use .1" header pins but again you could solder the wires to them and they are also on the edge so right angle pins can be used. I know that the micro usb's can be a pain to solder so there are also .1" header pinouts for the scales. The resistors can either be 1/4w through hole or 1206 smd'd. I am not sure what i will be using the analog 6 pin for yet but it has a pinout with gnd and 5v. The power input has solder pads or .1" header pins and sends input power to the fan so it if using a fan use the same voltage the fan requires. A 4 pin cpu fan is what is intended as the pcb will be able to control if it is on or off and speed.

 

[BeardedBrews]

Hey Krash,

I'm putting together an upgrade to my kegerator and wondered if your project was still active. I love the idea of knowing how much beer I've got left without having to pick up my kegs.

<edit> I guess I could have checked your website, looks like it's coming along. Can't wait for the first round of orders! http://krashkropp.com/bn-beer-homebrew/


-B

 

[krashkropp]

Hey everyone. I am still working on this project and have expanded the board some. I will make a GUI for windows computer or tablet with USB interface. 8 scale ports instead of 6. Mostly surface mount parts. Expanded memory. Power from USB. Any fan not just PWM fans. Proximity sensor for door sensing and interior light. Sorry for taking so long on this board I will be working hard on it to have something ready before October.

 

[krashkropp]

The boards have been sent out and I should have them back and soldered in 2-3 weeks. I will be writing code for serial display first, 16x2 LCD with buttons second, and hopefully bluetooth last.

 

[BeardedBrews]

Bump - Hadn't seen any updates lately, how did the new boards turn out?

 

[krashkropp]

The last board had header pins for Bluetooth and still used the ds18b20 sensor.
I fully populated a new board with a HM-11 bluetooth module and si7021.
The new temp sensor also has an accurate humidity sensor and refreshes much faster.
This will be the first one I mount in my Keezer and intend to have everything functioning except the GUI in a few weeks.
I also changed from 1, 5mm round led to 3 warm white surface mount leds each about as bright as an iphones led.
The code is almost done. I need to make a function to track scale drift. I have an extra PCB of this revision if anyone wants to solder it up and help development. The only issue I know of is the bluetooth needs to be shutdown with a solder blob to upload code since they use the same serial pins. Eventually I will add a MOSFET and have the atmega control this.

 

[krashkropp]

I have this board in my Keezer and have noticed that the fan Is important for temperature measurements. Also that the fan is not powerful enough on 5v it moves air but I don't think more effort would be wasted. I have added a switching boost ic to bring up the 5v rail to 12v and it will supply fans up to .5A but .2-.3 seems plenty. I also added a button to toggle threw the future lcd display. The leds are really bright and work great. I have moved the bluetooth to other pins so usb and bluetooth can both be used. The biggest problem so far is the si7021 onboard temp sensor. I reads high with the location I have mounted it and think the ds18b20 probed sensor will be the better way to read the keezer temp. The last thing I added was pins for a pressure transducer to measure Co2 psi. The current pcb is available from OSH park just search "keezer517rip"
If you want to build Let me know and I will help with what I can.

 

[raysmithtx]

I have ordered the board. Where can I find info on downloading the program you use and instructions on how to put that into the chip on the board?

 

[krashkropp]

I have added some info on my page with A BOM and PCB CAD file. I will try to have The current version of the code on there as well an a day or two. I Will Also try to have some basic instructions for installing the boot loader and firmware.

http://krashkropp.com/bn-beer-homebrew/

 

[raysmithtx]

I have added some info on my page with A BOM and PCB CAD file. I will try to have The current version of the code on there as well an a day or two. I Will Also try to have some basic instructions for installing the boot loader and firmware.

http://krashkropp.com/bn-beer-homebrew/

Perfect. Thank you.

 

[raysmithtx]

The boards arrived yesterday. I'll begin soldering all the components on over the next week or so.

Any updates on posting the source code? Any other tips would also be helpful.

 

[krashkropp]

Nice hope it all goes well. The source code is at the top of this page http://krashkropp.com/bn-beer-homebrew/
For soldering there are some small pins, and a stencil from https://www.oshstencils.com/#%20
helps but costs more money. probably the hardest ic is the usb/UART cp2102n. I prefer solder paste for pcb work. For most of the components I put a dot on the pads and set the part in the paste after all the parts are set you can use a heat gun or toaster oven(don't use the toaster oven for food after or so i'm told.)
When programming use an arduino uno to burn the bootloader(arduino nano) via the pads on the back. That will set the fuses and let you program threw the usb it also makes it use the external crystal instead of the internal. The workaround is to use an existing arduino nano ic. Heat the board up from the bottom with a heat gun and pluck the atmega328p chip off. If you use that chip it will have the bootloader already burned into it. Make sure to download and install the cp2102n driver for your computer so you can load the firmware. Let me know if you run into any problems and ill do my best to help.

On another note I have almost finished the previously mentioned revision with a 12v fan set up. I should have it ordered in a day or two and can make some more progress on the code.
Things to change
-timeout on leds from 10 seconds to 5 min
-ds18b20 to main temp sensor
-add second ds18b20 to outside temp sensor
-si7021 to pcb temp sensor

please let me know any suggestions.

 

[raysmithtx]

Thanks for the information. I hope to start working on this in a week or so. Looking forward to it.

Nice hope it all goes well. The source code is at the top of this page http://krashkropp.com/bn-beer-homebrew/
For soldering there are some small pins, and a stencil from https://www.oshstencils.com/#%20
helps but costs more money. probably the hardest ic is the usb/UART cp2102n. I prefer solder paste for pcb work. For most of the components I put a dot on the pads and set the part in the paste after all the parts are set you can use a heat gun or toaster oven(don't use the toaster oven for food after or so i'm told.)
When programming use an arduino uno to burn the bootloader(arduino nano) via the pads on the back. That will set the fuses and let you program threw the usb it also makes it use the external crystal instead of the internal. The workaround is to use an existing arduino nano ic. Heat the board up from the bottom with a heat gun and pluck the atmega328p chip off. If you use that chip it will have the bootloader already burned into it. Make sure to download and install the cp2102n driver for your computer so you can load the firmware. Let me know if you run into any problems and ill do my best to help.

On another note I have almost finished the previously mentioned revision with a 12v fan set up. I should have it ordered in a day or two and can make some more progress on the code.
Things to change
-timeout on leds from 10 seconds to 5 min
-ds18b20 to main temp sensor
-add second ds18b20 to outside temp sensor
-si7021 to pcb temp sensor

please let me know any suggestions.

 

[Ruvort]

Nice hope it all goes well. The source code is at the top of this page http://krashkropp.com/bn-beer-homebrew/
For soldering there are some small pins, and a stencil from https://www.oshstencils.com/#%20
helps but costs more money. probably the hardest ic is the usb/UART cp2102n. I prefer solder paste for pcb work. For most of the components I put a dot on the pads and set the part in the paste after all the parts are set you can use a heat gun or toaster oven(don't use the toaster oven for food after or so i'm told.)
When programming use an arduino uno to burn the bootloader(arduino nano) via the pads on the back. That will set the fuses and let you program threw the usb it also makes it use the external crystal instead of the internal. The workaround is to use an existing arduino nano ic. Heat the board up from the bottom with a heat gun and pluck the atmega328p chip off. If you use that chip it will have the bootloader already burned into it. Make sure to download and install the cp2102n driver for your computer so you can load the firmware. Let me know if you run into any problems and ill do my best to help.

On another note I have almost finished the previously mentioned revision with a 12v fan set up. I should have it ordered in a day or two and can make some more progress on the code.
Things to change
-timeout on leds from 10 seconds to 5 min
-ds18b20 to main temp sensor
-add second ds18b20 to outside temp sensor
-si7021 to pcb temp sensor

please let me know any suggestions.

Has there been any more progress on this project? I am very interested in it and would love to learn how to implement it in a future build.

 

[krashkropp]

Yes Ruvort I have finished the updates and made samples I had 1 trace on the pcb from the bluetooth that was creating problems for the usb to reset. That has been fixed and I have bought 100 pcb's. After I assemble and test 1 I will have the pcb's for sale on my website krashkropp.com I hope to have that done sometime next week. I have made a lot of progress on the code. The lcd is now functional and the blutooth will alter its settings automatically the first time it runs. It can also save beer names so switching between displays(lcd, windows, bluetooth) will all reflect a change made from 1. The 12v fan works great. I will make a new page on my site when I have it ready with all the details. I plan on selling the pcb's and some parts. If there is enough people who want it fully assembaled I might have a small batch made please let me know if you want one or more and if there are any other questions about the current design.