I hooked up the Aurora Uno PVI-2000 solar inverter to a laptop with an RS-232 serial cable. Note that we need an RS-232 cable with a male connector on one end and a female connector on the other end. It also needs to be a straight connection, i.e. no cross between RX and TX. If you don’t have such as cable handy, you might link two cross cables to acquire a straight cable.
Curt Blank has made an open source Linux program called aurora that uses this connection to get readouts from the inverter. The program is included in the Ubuntu packages since 10.04 LTS, so it is really easy to install:
sudo apt-get install aurora
The serial connection on my laptop is called /dev/ttyS0 by Linux, so this is what we use as one of the parameters. Another required parameter is the address of the inverter. Several inverters might be present in a solar installation, so an address is needed to target a specific one. Note that this is only relevant if they are linked together with RS-485 cables. In my case there is only one and the inverter has address 2.
Let’s start with the energy in the last 10 seconds:
# aurora -a 2 -j /dev/ttyS0 Energy in the last 10 seconds (Joules) : 1948.365882
More interesting is the energy produced for today, weekly, monthly, yearly and since the inverter was installed:
# aurora -a 2 -e /dev/ttyS0 Daily Energy = 0.094 KWh Weekly Energy = 0.094 KWh Monthly Energy = 12.447 KWh Yearly Energy = 12.471 KWh Total Energy = 12.469 KWh Partial Energy = 12.444 KWh
There are also readings about voltage and current. To be honest, I don’t understand the input 2 readings because there is nothing connected there.
# aurora -a 2 -d /dev/ttyS0 Input 1 Voltage = 184.667801 V Input 1 Current = 2.804785 A Input 1 Power = 517.953552 W Input 2 Voltage = 0.650100 V Input 2 Current = 1.859635 A Input 2 Power = 1.208949 W Grid Voltage Reading = 225.644196 V Grid Current Reading = 1.965952 A Grid Power Reading = 458.323853 W Frequency Reading = 49.991001 Hz. DC/AC Coversion Efficiency = 88.3 % Inverter Temperature = 38.024002 C Booster Temperature = 35.868004 C
There is also a Windows program made by Power One that shows current and historical readings called Aurora Communicator. A partial screenshot is shown below with some values when the sun shines brightly (for a November day that is).
The screenshot below shows the readings for a complete day. The lower graph shows the Watts (W) produced at each timestamp and the upper graph shows the accumulated Watt hours (Wh) values.