python-itho-wpu

A python library and a set of command line tools to communicate with an Itho WPU.

Hardware installation

See the pislave project

Software installation

1. Install Raspberry Pi OS Lite

2. Enable SSH and I2C using raspi-config

3. Install and configure the required software

   apt-get install \
       git \              # To clone this repository
       pigpiod \          # Pigpio daemon to communicate over the I2C bus
       python3-pigpio \   # Python module to talk to the pigpio daemon
       python3-pyodbc \   # Python module to access an ODBC database
       odbcinst1debian2 \ # Library for accessing ODBC config files (odbc-mdbtools dependency)
       sqlite3 \          # To store a subset of the Itho database in SQLite
       direnv \           # Environment variable manager to store credentials for InfluxDB
       python3-influxdb   # To export measurements to InfluxDB
   
   # Set the sample rate value of pigpiod to 10 microseconds to decrease CPU usage
   sed -i -e 's/ExecStart=.*/ExecStart=\/usr\/bin\/pigpiod -l -s 10/' /lib/systemd/system/pigpiod.service
   
   # Enable pigpiod service
   systemctl enable pigpiod
   

   Install version 0.9.3-1 of odbc-mdbtools

   SOURCE=http://snapshot.debian.org/archive/debian/20210503T151244Z
   ARCH=$(dpkg --print-architecture)
   VERSION=0.9.3-1
   curl -OL ${SOURCE}/pool/main/m/mdbtools/odbc-mdbtools_${VERSION}_${ARCH}.deb
   curl -OL ${SOURCE}/pool/main/m/mdbtools/libmdb3_${VERSION}_${ARCH}.deb
   curl -OL ${SOURCE}/pool/main/m/mdbtools/libmdbsql3_${VERSION}_${ARCH}.deb
   dpkg -i libmdb3_${VERSION}_${ARCH}.deb libmdbsql3_${VERSION}_${ARCH}.deb odbc-mdbtools_${VERSION}_${ARCH}.deb
   

   When executing convert-itho-db.py with mdbtools version ...

   • 0.7.1-6 (Debian Buster) it fails with: ValueError: the query contains a null character
   • 0.9.1-1 (Debian Bullseye) it fails with: Segmentation fault

4. Reboot the Raspberry Pi

   reboot
   

5. Install python-itho-wpu

   git clone https://github.com/pommi/python-itho-wpu.git
   cd python-itho-wpu
   

6. Extract $_parameters_HeatPump.par from the Itho Service Tool. This is a Microsoft Access database containing details about all WPU versions.

   • Download it directly:

     curl -o HeatPump.par "https://servicetool.blob.core.windows.net/release/Parameters/\$_parameters_HeatPump.par"
     

   • Or download the Itho Service Tool and execute AzureBootloader.exe to retrieve the full Itho Service Tool application. $_parameters_HeatPump.par is located in the Parameters directory. Save it as HeatPump.par in the python-itho-wpu folder.

7. Convert the Microsoft Access database to an SQLite datbase. The SQLite database is used by python-itho-wpu.

   ./convert-itho-db.py --itho-db HeatPump.par
   

Example usage of python-itho-wpu

• Get the NodeID of the WPU

  # ./itho-wpu.py --action getnodeid
  ManufacturerGroup: 1, Manufacturer: HCCP, HardwareType: WPU, ProductVersion: 25, ListVersion: 11
  

• Get the Serial number of the WPU

  # ./itho-wpu.py --action getserial
  Serial: 408
  

• Get the Datalog of the WPU

  # ./itho-wpu.py --action getdatalog
  Buitentemp (°C): 8.0
  Boilertemp Onder (°C): 24.23
  Boilertemp Boven (°C): 51.68
  Verdamper Temp (°C): 19.84
  Zuiggas Temp (°C): 21.7
  Persgas Temp (°C): 30.22
  Vloeistof Temp (°C): 18.67
  Temp Naar Bron (°C): 21.09
  Temp Uit Bron (°C): 19.75
  ...
  

• Retrieve a single setting from the WPU

  # ./itho-wpu.py --action getsetting --settingid 1
  1. Hardware Configuratie: 70 (min: 0, max: 65535, step: 1)
  

• Retrieve all settings from the WPU

  # ./itho-wpu.py --action getsettings
  0. Niet Gebruikt: 0 (min: 0, max: 65535, step: 1)
  1. Hardware Configuratie: 70 (min: 0, max: 65535, step: 1)
  2. Jaar Inbedrijfstelling: 2010 (min: 2004, max: 2099, step: 1)
  3. Datum Van Inbedrijfstelling: 101 (min: 0, max: 3112, step: 1)
  4. Max Handbedieningstijd (min): 0 (min: 0, max: 600, step: 1)
  5. Vorsttemp (°C): 2.0 (min: -10.0, max: 10.0, step: 0.1)
  6. Offset Voor Vorst Temp (K): 2.0 (min: 0.0, max: 10.0, step: 0.1)
  7. Differentie Van Vorst Om Elektrisch Element Te Starten (K): 1.5 (min: 0.0, max: 10.0, step: 0.1)
  8. Fout Reset Tijd (min): 120 (min: 1, max: 1440, step: 1)
  9. Loginterval Tijd (sec): 5 (min: 1, max: 300, step: 1)
  ...
  

• Change a setting of the WPU

  # ./itho-wpu.py --action setsetting --settingid 139 --value 48
  Current setting:
  139. Blokkade Tijd Van Verwarmen Naar Koelen (uur): 24 (min: 0, max: 168, step: 1)
  Setting `139` will be changed to `48`? [y/N] y
  Updating setting 139 to `48`
  Are you really sure? (Type uppercase yes): YES
  139. Blokkade Tijd Van Verwarmen Naar Koelen (uur): 48 (min: 0, max: 168, step: 1)
  

Exporting measurements

InfluxDB

Assuming InfluxDB is running on the Raspberry Pi as well.

1. Configure a .envrc file

   cat > .envrc <<EOT
   export INFLUXDB_HOST=127.0.0.1
   export INFLUXDB_USERNAME=user
   export INFLUXDB_PASSWORD=password
   export INFLUXDB_DATABASE=itho
   EOT
   

2. Allow direnv to load environment variables from the .envrc file

   direnv allow
   

3. Execute itho-wpu.pu and export to InfluxDB

   ./itho-wpu.py --action getdatalog --export-to-influxdb
   

4. Alternatively run this in a 5 minute cronjob (the console output is written to /var/log/itho.log)

   cat > /etc/cron.d/itho <<EOT
   PATH=/usr/bin:/bin:/usr/sbin:/sbin
   
   */5 * * * * root cd /root/python-itho-wpu && DIRENV_LOG_FORMAT='' direnv exec . ./itho-wpu.py --action getdatalog --export-to-influxdb >> /var/log/itho.log
   EOT
   

Grafana Dashboard

The measurements collected in InfluxDB can be displayed using a Grafana dashboard.

Download: direct link, grafana.com