Method for detecting asymmetry of parallel strings of solar modules of solar system for checking e.g. installation of solar system in rooftop, involves determining presence of asymmetry of parallel strings based on asymmetry value

摘要

The method involves measuring current flowing through parallel strings of solar modules of a solar system by using a current sensor (30). An asymmetry value for one of the strings is determined as quotient from the current flowing through one of the strings in an idle condition of the strings and current difference between the current flowing through the string and comparison current flowing through another string. The current difference is determined during maximum output of the strings, and the presence of asymmetry of the parallel strings is determined based on the asymmetry value. Independent claims are also included for the following: (1) a software for programming a controller of a central unit of a solar system (2) a central unit for a solar system.