Service for WeeWX to retrieve air quality data from the airQ device of Corant GmbH
PM1.0, PM2.5, PM10.0, TVOC, CO, CO2, O2, O3, NO2, H2S, SO2, noise, health index, performance index, temperature, humidity, dewpoint, air pressure
The following Python modules are necessary to use this extension:
- base64
- Cryptodome.Cipher
- http.client
- json
- threading
It depends on the distribution you use whether those modules are installed by default. For Debian this installation should do it:
sudo apt-get install python3-cryptodome
User Hartmut was successful with that:
sudo apt-get install build-essential python3-dev
pip3 install pycryptodomex
python3 -m Cryptodome.SelfTest
-
download
wget -O weewx-airQ.zip https://github.com/roe-dl/weewx-airQ/archive/master.zip
-
run the installer
sudo wee_extension --install weewx-airQ.zip
-
edit configuration in weewx.conf
[airQ] query_interval = 5.0 # this is the default, if option is missing volume_mass_method = 1 # 0 - temp/pressure independent factor [[first_device]] host = replace_me_by_host_address_or_IP password = replace_me #prefix = replace_me # optional #altitude = value, unit # optional, default station altitude #query_interval = value # optional, if different from general setting [[second_device]] ... ... [Engine] [[Services]] prep_services = ... ,user.airQ_corant.AirqUnits data_services = ... ,user.airQ_corant.AirqService ...The section names can be any name. It need not be something like
[[first_device]]. We recommend to use some reference to the location of the device like[[bedroom]],[[livingroom]], or the like. -
restart weewx
sudo /etc/init.d/weewx stop sudo /etc/init.d/weewx start
Using this extension you get the readings out of the airQ measuring device and can
- save them to the database
- display them using tags in skins
- display them in graphs
Most of the the observation types provided by the airQ device are predefined within WeeWX. If no special configuration besides host address and password is provided the readings are stored to those observation types.
If you have more than one airQ device, you need different names of the
observation types for each of them. That's the prefix for.
Imagine there are 3 airQ devices, one outside, one in the bedroom and
one in the living room. Your could configure the outside device without
prefix to put co, co2, no2, noise, o3, pm1_0, pm2_5,
pm10_0, and so2 into the predefined columns of the WeeWX database.
For the bedroom device you could set prefix = bedroom. So you get
bedroom_co, bedroom_co2 etc. for that device. And for the living
room device you could set prefix = livingroom. So you get
livingroom_co, livingroom_co2, etc. for that.
This extension comes with a special configuration tool called airq_conf.
The tool is based on the WeeWX wee_database tool and provides means
to add the necessary columns according to the prefix setting to the
database or drop them from it. See below for details.
If you run several instances of WeeWX and transfer readings from one
to the other by MQTT, parallel database access, or something, then
you also need to install
weewx-airQ at the target system and include user.airQ_corant.AirqUnits
in line prep_services, but omit user.airQ_corant.AirqService
in line data_services.
That is because in initialization of the weewx-airQ
extension several additional units and conversations are
added to the lists in units.py They are neccassary to convert
between ppm and ppb as well as µg/m3, mg/m3,
and g/m3, respectively.
The observation types described below can be used for tags as described in the WeeWX Customization guide.
Example: $current.TVOC
To create diagrams you need to include additional sections into the [ImageGenerator] section of skin.conf. This is an example:
[[[dayPM]]]
[[[[pm1_0]]]]
[[[[pm2_5]]]]
[[[[pm10_0]]]]
The result is as follows:
Dependent on hardware configuration the following observation types are provided. The names are given as if no prefix is specified:
- airqDeviceID: (provided if included in
[StdWXCalculate]only) device ID of the device - airqStatus: (provided if included in
[StdWXCalculate]only) sensor error messages or "OK" if none - airqBattery: battery status (actually not used)
- co: CO concentration
- co2: CO2 concentration
- dCO2dt: CO2 changing rate
- dHdt: absolute humidity changing rate
- airqDewpoint: dewpoint
- airqDoorEvent: (experimental) door opened or closed
- h2s: H2S concentration
- airqHealthIdx: health index (special index according to a newly developed algorithm from the manufacturer)
- airqHumidity: relative humidity
- airqHumAbs: absolute humidity
- airqMeasuretime: duration of the last measuring cycle
- no2: NO2 concentration
- o3: O3 concentration
- o2: O2 concentration
- airqPerfIdx: performance index (special index according to a newly developed algorithm from the manufacturer)
- pm1_0, pm2_5, pm10_0: particulate matter
- cnt0_3, cnt0_5, cnt1_0, cnt2_5, cnt5_0, cnt10_0: amount of particles of the appropriate size
- TypPS: typical particle size
- airqPressure: air pressure
- airqAltimeter altimeter value (air pressure corrected by altitude, software calculated, not received from the device)
- airqBarometer: barometer value (air pressure corrected by altitude and outside temperature, software calculated, not received from the device)
- so2: SO2 concentration
- airqNoise: sound level
- airqTemp: temperature
- TVOC: volatile organic compounds concentration (including Corona viruses)
- airqUptime: uptime of the device
If a prefix is provided "airq" is replaced by the prefix. If the name does not start by "airq" the prefix is prepended to the name.
--device=DEVICE: airQ device to set/get configuration for--config=CONFIG_FILE: use configuration file CONFIG_FILE. Default according to the way of WeeWX installation--binding=BINDING_NAME: Use binding BINDING_NAME. Default iswx_binding.
airq_conf --help: display usage instructionsairq_conf --device=DEVICE --print-config: read the device configuration and display
The wee_database utility allows adding columns to the database one by one
only. As the airQ device provides a lot of additional observation types,
this is quite uncomfortable. The airq_conf tool provides the possibility
to add all the additional columns in one step. It regards the prefix
configuration option. By using the original WeeWX
functions for that, it should be safe. Nevertheless, backups are alsways a
good idea. And stop WeeWX for that.
CAUTION: Stop WeeWX and make a backup of the database before using these commands.
airq_conf --device=DEVICE --add-columns: add the necessary columns to the databaseairq_conf --device=DEVICE --drop-columns: drop the columns from the database
The configuration utility comes with an option to create a simple skin
based on the Seasons skin and the settings in weewx.conf. It creates
a separate page for each device configured showing the current readings
and diagram images. Diagram are only possible for observation types
that are saved to the database.
airq_conf --create-skin
The command does not change weewx.conf. If you want to use this
skin you need to add the following section into the StdReport section
of weewx.conf.
[[airqReport]]
enable = true
skin = airQ
lang = de
unit_system = METRIC
HTML_ROOT = /var/www/html/weewx/airQ
The lang option must have the same value as it has for the Seasons
skin.
For observation types that are not saved to the database, no diagram can be created. In these cases the diagram is empty.
Note: The language and unit system options are available from WeeWX version 4.6 alpha on, only. Starting with WeeWX version 4.6 beta, the localization changed vom bracket to function style. That is automatically honored.
Example:
Those commands change configuration settings within the airQ device.
airq_conf --device=DEVICE --set-location=station: set the location of the airQ device to the station locationairq_conf --device=DEVICE --set-location=LATITUDE,LOGITUDE: set the location of the airQ device to latitude and longitude providedairq_conf --device=DEVICE --set-roomsize=HEIGHT,AREA: set the room size dataairq_conf [--device=DEVICE] --set-ntp=NTP_SERVER: set the NTP serverairq_conf [--device=DEVICE] --set-ntp=de: set the NTP server to the official german server of PTB.