This paper presents implemented solutions for monitoring driving factors concerning degradation and ageing during normal operation of a photovoltaic (PV) inverter in a test environment. The monitoring focus is on capacitors and semiconductor modules due to their high failure rates in inverter systems. The
implementation of online measurements mainly based on the temperature for the capacitors and powermodules. Additional offline measurements are intended to support the results. Consequently, various measurement solutions are described in detail along with initial results form an already running system.