SMA provides auxiliary power supplies for the redundant board supply and independently controllable air conditioning for the tram-trains of RegioTram Kassel. The tram-trains designed as two-system and hybrid vehicles are manufactured by ALSTOM LHB in Salzgitter and belong to the family of regional light rail vehicles RegioCITADISTM.

The auxiliary power supplies belong to SMA's product family MEE-NTSD for regional traffic and are based on the MEE-NT platform. SMA has thus an innovative and sophisticated modular platform proven in daily use for auxiliary power supplies in different applications.

Each vehicle for RegioTram Kassel has three auxiliary power supplies. Two MEE-NTSD RegioTram "Generic" are responsible for the partly redundant AC and DC board supply of the vehicle. One MEE-NTSD RegioTram "Air Con" provides an independent, variable frequency and variable voltage supply for each of the three air-conditioning units of the vehicle.

The tram-trains for RegioTram Kassel are designed as two-system and hybrid vehicles. The auxiliary power supply must thus comply with the requirements for both trams and mainline trains. In addition, challenges such as low weight, compact design, natural cooling under partial load conditions, minimum noise emission and high availability arose.

Conclusion
The MEE-NTSD RegioTram “Generic” and “Air Con” are an innovative, sophisticated and reliable solution for the tram-trains for RegioTram Kassel that is optimized for the vehicle concept. Specifically the natural cooling under partial load conditions and the “whisper mode” are outstanding system features.