SCD30_ReefPi

Full Reef-Pi interface to Sensirion SCD30 air quality sensor. Provides SCD30 base class for communication, command line tool for settings and control, a service for regular data acquisition and an install script.

Installation

• in SSH command console type:

• sudo wget -c https://github.com/Sral931/SCD30_ReefPi/releases/download/1.1/SCD30_ReefPi_1.1.zip

• sudo unzip SCD30_ReefPi_1.1.zip

• sudo bash install_SCD30.sh

• the install script will copy all files, start the necessary service and clean up the install files afterwards

• In Reef-Pi go to Configuration->Drivers

• create 3 file drivers in Reef-Pi:

  • Name appropriately (e.g. "SCD30_CO2", "SCD30_temp" and "SCD30_hum")
  • Type: "file-analog"
  • Paths (for each filedriver respectively):
    • "/var/lib/reef-pi/SCD30/co2.dat"
    • "/var/lib/reef-pi/SCD30/temp.dat"
    • "/var/lib/reef-pi/SCD30/hum.dat"

• go to Configuration->Admin and reload

• go to Configuration->Connectors

  • create 3 Analog-Inputs:
    • Name appropriately (e.g. "SCD30_CO2", "SCD30_temp" and "SCD30_hum")
    • Driver: the 3 file-drivers you have created before
    • Pin: 0

• go to Configuration->Admin and reload

• go to pH

• add 3 "pH" values using the analog-inputs you have just created

Operation and Settings

• to access the command line tool type into an SSH command line tool (I use PuTTY):
• cd /var/lib/reef-pi/SCD30
• ./SCD30Control -help
• you will see a listing of all available commands
• Examples:
  • print current measurements:
    • ./SCD30Control -meas
  • set altitude to 75m (will turn off exact pressure offset using ./SCD30Control -start 1000)
    • ./SCD30Control -altitude 75
  • set temperature offset to 2.8 °C
    • ./SCD30Control -tempoff 280

Notes

• temperature offset:
  • as you will likely put the board into an enclosure this enclosure will warm up and have a higher temperature than the surrounding air
  • to compensate, wait half an hour to let the temperature settle on equilibrium
  • then lok at the measurement value (either in Reef-Pi or using ./SCD30Control -meas)
  • calculate how much the temperature is above the actual room temperature (in my case 2.8°C)
  • set this by using: ./SCD30Control 280 (single digits represent 0.01°C, e.g. 100 is 1.0°C)
• future development:
  • create a similar interface for a BMP280 air pressure sensor and feed this information to the SCD30 sensor as well