Using the TonidoPlug² as a Datalogger for Photovoltaic Panels

I managed to setup my TonidoPlug² (TP2) as a data-logger that automatically uploads live statistics of my solar panels to pvoutput.org. This post details the steps I followed to run sma-bluetooth on the TP2 .

After ssh'ing to your TP2, prepare a build environment on the plug pc:

• follow the steps in: http://www.tonido.com/communitywiki/doku.php?id=advanceduses:setupbuildenvironment
• step 4 & 5 are slightly outdated:
  • (4a) I had to install the deb-multimedia-keyring package first:

    apt-get install deb-multimedia-keyring 
    

  • (4b) the url for wget is diffent:

    wget http://www.debian-multimedia.org/pool/main/d/debian-multimedia-keyring/debian-multimedia-keyring_2010.12.26-3_all.deb 
    

  • (5) dpkg -i debian-multimedia-keyring_2010.12.26-3_all.deb

After that you can follow the steps I detailed in my previous post: http://michael-peeters.blogspot.com/2012/04/sb-inverter-bluetooth-connection-on.html. Summarized:

• compile sma-bluetooth:

  wget http://sma-bluetooth.googlecode.com/files/sma-bluetooth-0.17b.tar.gz 
  tar -xzf sma-bluetooth-0.17b.tar.gz 
  cd sma-bluetooth-0.17 
  sudo apt-get install mysql-server mysql-client  libmysqlclient-dev 
    # (don't forget to enter a non-blank password for mysql!) 
   
   gcc -c smatool.c 
   gcc smatool.o -L/usr/lib -lmysqlclient -lbluetooth -lcurl -lm -o smatool 
  

• edit the configuration. This can be tricky! Check the details first.

  # nano ./smatool.conf 
  

• install the mysql tables:

  ./smatool --INSTALL 
  

• run / debug errors:

  ./smatool -d -v 
  

Once smatool runs OK from the command-line, you can consider scheduling the run in cron.

• create a smatool.cron file in your home-directory. Contents:
  

  # /etc/cron.d/smatool: crontab entries for smatool (monitoring of Sunnyboy Grid Interactive Inverter) 
   
  SHELL=/bin/sh 
  PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/home/smatool/bin 
   
  # The following line runs the smatool every 15 minutes between 0500 and 2300 and logs all output to the /var/log/smatool.log file. 
  */15 5-23 * * *   root cd /root/sma-bluetooth-0.17; ./smatool 2>&1 | logger -t smatool -p local5.info 
  

• activate the new cron entry:

  cp ./smatool.cron /etc/cron.d/smatool 
  chmod 744 /etc/cron.d/smatool 
  

• checkout /var/log/syslog for errors
• each run is logged in /var/log/syslog

The result:



Possible improvements:

• sma-bluetooth requires mysql which is a relatively heavy database for a plugpc. Sqlite would be a better choice. I experimented with the excellent fork http://rcphills-sma-bluetooth-dbabstraction.googlecode.com/ that supports sqlite, but the connection to pvoutput.org didn't work anymore.
• the current setup does too much I/O preventing the SATA HD to sleep. Unfortunately booting from an external USB flash disk is not easy on TP², so I'll have to investigate other alternatives.