SMA Tripower Inverter- Intelligent String Failure Detection

Published Categorised as Case Studies

Dimplex50kWPVLothian Renewables were asked to rectify a “fault” on 50kW roof mounted PV system where one of the 3 SMA Tripower 15000TL inverters was showing an error code and not producing any output.

” String B defective

 Check generator”

After some initial system checking the problem was diagnosed to an issue with the Intelligent String Failure Detection function. The 15000TL is a top range inverter manufactured by SMA, the world’s largest inverter manufacturer. The Tripower range of inverters have a function that monitors the individual strings that are connected to it and will display an error warning on the inverter and via an internet connection if fitted ,to alert the operator of the plant. This function is configured during commissioning and requires the inverter to “learn” the voltage characteristics of the various strings, a process that can take up to 14 days. Once “learned” any deviation from this stored characteristic will trigger an alert. If the “learning” period has taken place during a particularly sunny period the inverter may mistake low panel performance in periods of low sunlight – mid-winter for example or periods where the panels are covered in snow- as an error.

The issue is easily rectified by accessing the inverter via. Sunny WebBox or Sunny Explorer and reinitiating the “learning “phase.

The system pictured above was made up of 168 Dimplex PV panels, a 20 tube Dimplex solar thermal collector can be seen in the foreground.