INSTALL

To use this utility you need a Fronius PV inverter with an RS-232 card.
This is the "Fronius Interface Card easy" which should be available
from wherever you got your inverter.

http://www.fronius.com/cps/rde/xchg/SID-C46941A8-5BC164B9/fronius_international/hs.xsl/83_16258_ENG_HTML.htm

You'll also need a serial null-modem cable and perhaps a USB<=>RS232
converter lead (if we assume you're using something like a SheevaPlug,
which doesn't have an RS232 port).

Connect up the Fronius to a suitable serial port on your computer and
take note of which serial port this is (e.g. /dev/ttyUSB0)

Download and compile the Fslurp utility from:

http://fslurp.sourceforge.net/

Install the binary in /usr/local/bin.  You'll need to give yourself
permission to access the serial port.  On Debian you can do this with:

  sudo adduser <your user name> dialout

You'll then need to log out and back in again to get the upgraded
permission.

Test the basic configuration with the following command:

  fslurp -p /dev/ttyUSB0 -r all

and you should see all the current readings from your inverter.  Note that
if it's dark the inverter goes completely to sleep and you'll get a message
about "No active inverter found".  If the inverter is just waking up you'll
get a lot of values reading "overflow".  Once you have enough sun to be
generating power you should get a full set of readings.


Once you've got fslurp working you need to decide where you want your
data files to go.  Anywhere will do - just create a directory in your
chosen location.

Copy all the files from the "bin" directory in this software distribution
to /usr/local/bin, and all the files from the "etc" directory to
/usr/local/etc.

Now you need to visit http://pvoutput.org/ and register your system.
You will be allocated a system id.  At the bottom of your Account Settings
page, you'll find a section headed "API Settings".  Change "API Access"
here to "Enabled" and click the "New Key" button to generate an API Key.
Copy this API Key - be aware that it's actually slightly longer than
the field so you need to make sure you select the whole key - and save
it.

Now edit /usr/local/etc/processpv.cfg.  You need to set the following
variables:

PVPORT          The serial port to which your inverter is connected
PVDATADIR       The directory where you want the data files
PVDEDUCT        How many watts to deduct from each reading
PVID            Your system id from pvoutput.org
PVKEY           Your API Key from pvoutput.org

And a bit of luck things should now be ready to work.  Try executing
/usr/local/bin/slurptocsv.  That should take a current set of readings
from your inverter and save them to your data directory.  Then
try typing:

  processpv.rb <name of data file>

and you should see some stats about your output.

Finally you need to set up cron to run your scripts regularly.  There's
a sample crontab supplied, and if you want to use that (and don't already
have any cron jobs set up) you just need to type:

  crontab crontab

and it will be installed on your system.

A word about PVDEDUCT.  It appears that the Fronius inverter reports the
wattage which it is generating, before it uses some of that wattage to
power its own internals.  As a result, the total kWh figure at the end of the
day consistently disagrees with the figure given by the official calibrated
meter in the installation.  I find that by setting PVDEDUCT to 30 (Watts), I
can get the two to agree pretty closely.  YMMV.