blakeclewis / kiln_logger

raspberry pi kiln logging

kiln_logger

Heat is dangerous! Evaluate the risk and make your go/no-go decision!

I have had issues with the thermocouple chip getting too hot when air temp is above 90F. It is in a metal box, 2' away from the kiln. Last firning, when the kiln was within 30C of cone 6, it started under reading. I added a computer muffin fan to cool the electronics.

Parts and pieces: I think it adds up to ~ $70 and some shipping.

• Raspberry pi: any of these will work, $10 Zero W is cheapest, but a Pi 3b runs much faster and will give a desktop.

    https://www.adafruit.com/product/3775
  
    https://www.adafruit.com/product/3055
  
    https://www.adafruit.com/product/4027
  
    https://www.adafruit.com/product/3400
  

• 5V power supply: for the Pi

    https://www.adafruit.com/product/1995
  

• MicroSD card: you will also need a way to write the image, e.g. usb adapter

    https://www.amazon.com/SanDisk-microSDHC-Standard-Packaging-SDSQUNC-032G-GN6MA/dp/B010Q57T02/ref=sr_1_14?keywords=micro+sd&qid=1552005480&s=gateway&sr=8-14
  

• MAX31856 thermocouple module:

    https://www.adafruit.com/product/3263
  

• Female <=> Female jumper wires:

    https://www.adafruit.com/product/266
  

• 20x4 LCD w/ i2c backpack: it will print to console too.

    https://www.amazon.com/gp/product/B01GPUMP9C/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
    or
    https://www.adafruit.com/product/198
    https://www.adafruit.com/product/292
  

• High temperature (2372 F) type K thermocouple:

    https://www.amazon.com/Temperature-Thermocouple-Ceramic-connector-CR-06/dp/B0713X6XG3/ref=sr_1_25?keywords=k-type&qid=1551683054&s=gateway&sr=8-25
  

• Download Raspbien Stretch or newer and write it to the MicroSD:

    https://www.raspberrypi.org/downloads/raspbian/
    boot it up
    expand the partition, it ask on first boot
    configure network
    update software 'apt-get update' and 'apt-get upgrade'
  

Wiring:

• fritz: 'https://raw.githubusercontent.com/BlakeCLewis/kiln_logger/master/logger_bb.png'

• Pin-Out:

    Device	PI
    ----------	-------
    RPLCD VCC:	5V
    RPLCD GND:	GND
    RPLCD SDA:	GPIO 2
    RPLCD SCL:	GPIO 3
  
    MAX31856 3vo:	3.3v
    MAX31856 GND:	GND
    MAX31856 SDO:	GPIO 9
    MAX31856 SDI:	GPIO 10
    MAX31856 CS:	GPIO 8
    MAX31856 SCK:	GPIO 11
  

• Install project files:

    git clone [email protected]:BlakeCLewis/kiln_logger.git
  

• Install sqlite3:

    sudo apt-get install sqlite3
  

• Configure raspberry pi interfaces:

    sudo raspi-config
    #enable interfaces ssh, ic2 & spi
  

• Instal RPLCD for the 20x4 lcd:

    sudo pip3 install RPLCD
  

• Install MAX31856 Module:

    cd
    sudo apt-get update
    sudo apt-get install build-essential python3-pip python3-dev python3-smbus git
    git clone https://github.com/adafruit/Adafruit_Python_GPIO.git
    cd Adafruit_Python_GPIO
    sudo python3 setup.py install
    cd
    git clone [email protected]:johnrbnsn/Adafruit_Python_MAX31856.git
    cd Adafruit_Python_MAX31856
    sudo python3 setup.py install
  

• test modules:

    cd ~/kiln_logger
    python3 display.py
    python3 max31856_test.py
  

• create the database:

    sqlite3 ~/kiln_logger.sqlite3
    CREATE TABLE firelog(RunID number, datime datetime, t number);
    .schema
    .exit
  

• run the logger

    cd ~/kiln_logger
    ./logger.py -i <intger Run_ID> -s <interval in seconds>
  

• access data:

    ssh pi@<pi ipaddres>
    sqlite3 kilnlog.sqlite3
    select * from firelog where runid=420 order by datime asc;