Abstract: For inspecting polarities of poles of DC voltage sources, each pole being individually connected to one of separate input terminals of a combiner circuit, an inspection apparatus includes electric contacts each provided for one of the input terminals such that one of the poles of each DC voltage sources is each connected to one of the electric contacts, respectively. A signaling element when subjected to an electric signal emits a matching signal. One switching element per each of the at least two electric contacts forwards the electric signal if a polarity of a voltage present at the respective electric contact matches a polarity pre-set for the respective electric contact with regard to a reference potential, and blocks the electric signal if the polarity of the voltage does not match the pre-set polarity. The switching elements are electrically connected in series.

Abstract: For inspecting polarities of poles of DC voltage sources, each pole being individually connected to one of separate input terminals of a combiner circuit, an inspection apparatus includes electric contacts each provided for one of the input terminals such that one of the poles of each DC voltage sources is each connected to one of the electric contacts, respectively. A signaling element when subjected to an electric signal emits a matching signal. One switching element per each of the at least two electric contacts forwards the electric signal if a polarity of a voltage present at the respective electric contact matches a polarity pre-set for the respective electric contact with regard to a reference potential, and blocks the electric signal if the polarity of the voltage does not match the pre-set polarity. The switching elements are electrically connected in series.