Siemens has widened its portfolio of planetary gear units. The Planurex 3 is available in ten sizes, with a torque range from 1,700 to 5,450 kNm. This raises the highest torque in the standard modular system from the previous 2,600 kNm up to 5,450 kNm. The size grading is harmonised to reduce the jump in power ratings between different sizes. This makes a suitable torque and a suitable transmission ratio available for almost every application. The gear units also have the highest efficiency in their class. This has been achieved by increasing the torque density (Nm/kg) by an average of 17.2 per cent in comparison to the previous series. A compact design enables space-saving, high transmission ratios to be achieved. This not only reduces the weight, but also the stress on the gear unit and application. Planurex 3 is part of an Integrated Drive System (IDS), which is available as a complete solution, comprising motor, gear unit and coupling, combined with an oil supply system.