After using SMA’s Sunny Portal and Sunny Places web sites to monitor some central inverter PV systems I realized that I wanted more detailed information about system performance than these sites provided.
Specifically, I wanted to know how the individual PV strings in a system were performing so I could get a better idea of the effects of orientation, shading, and other issues. As a result I wrote two custom C# Windows applications to collect data and provide a graphical display of the DC power, current, voltage, and energy production of the individual trackers in the Sunny Boy TL series of inverters, although certain other inverter series should also be compatible.
The first application collects data from all inverters in the system via their Modbus TCP servers every 5 minutes and stores it in daily “history” files on the computer. The second application graphically displays data from these files for the selected day. For the most thorough results I run the data collection application 24/7, but in reality running it only during daylight hours would be sufficient. Since the graphical display application is not involved in data collection I only run it when I wish to view previously collected data. Examples of the graphical displays are provided below.
Power/Energy display for the three strings in a dual SB6000TL-US-22 system. Note the approximate 13% power/energy loss in the inverter2 (1) string due to all-morning chimney shading:
Composite Power/Energy display for the three strings in a dual SB6000TL-US-22 system:
Voltage display for the three strings in a dual SB6000TL-US-22 system:
Current display for the three strings in a dual SB6000TL-US-22 system:
Interested in my application?
If anyone is interested in using my applications I have no problem in sharing them free just for the fame and glory it will bring me 😉 Please write an email to SocialMedia@SMA.de and I will get back to you.
I’m always interested in enhancing and improving what I’ve done. So in case anyone has any requests for different inverter information monitoring, please let me know. I’m looking forward to your feedback and questions in the comment section.
You will find more information on SMA Developer.
Ray Mitchell (guest author)
Ray is a retired electronics engineer and programmer. He currently teaches programming part time at the University of California and he writes programs as a hobby.