It's called "NA Schutz"[1] and is required for all german micro-inverters by VDE-AR-N-4105:2018. Which in turn is national law following EU directive. [1] http

It's called "NA Schutz"[1] and is required for all german micro-inverters by VDE-AR-N-4105:2018. Which in turn is national law following EU directive. [1] https://de.wikipedia.org/wiki/Netz-_und_Anlagenschutz https://de.wikipedia.org/wiki/Netz-_und_Anlagenschutz