Siemens Aktiengesell Schaft

Siemens Aktiengesellschaft

Albrecht Wolf

Karsten Ahnert

Gernot-Dirk Almen

Bernd Flor

Franz Nagy

Nico Wohlrab

Norbert Fiedler

The invention relates to a motor starter () for an electric motor (), wherein the motor starter () comprises a first and a second phase (). Said motor starter and electric motor each have an associated switching apparatus () which each have an electromechanical switch () and a semiconductor switch () connected to form a bypass circuit. The electromechanical switches () and the semiconductor switches () are designed to be separately operable by a control unit (), and the first and the second phase () are connected to a passive overcurrent protection means (). The passive overcurrent protection means () has a fuse () for each phase. According to the invention, a measuring apparatus () is arranged in at least one of the phases () along the phase direction directly between the passive overcurrent protection means () and at least one of the switching apparatuses (). The invention further relates to diagnosis methods () with which defects in the motor starter () can be diagnosed during an activation sequence.

Motor starter and diagnosis method

Growing community of inventors

Grüna, Germany

Albrecht Wolf