Lyman, SC – SEW-EURODRIVE has engineered a new line of AC motors with modular components that can be configured to comply with any nation’s energy efficiency standards. The new DR family of motors will replace all other AC motors in SEW’s product line in 2009, providing engineers around the world with optimum energy-saving solutions for any application. The compact new motors can be integrated into SEW gearmotors, used as stand-alone motors or in decentralized control architectures.
SEW, which has been manufacturing motors since it was founded in Germany in 1931, was the first company in the world to manufacture industrial AC motors using die-cast copper technology. Since that breakthrough in 2002, SEW has been working to create a new generation of energy-efficient motors using materials like copper to lower electrical resistance and new designs to reduce energy losses in operation. Copper rotor cages, for example, allow a motor’s power rating to increase while maintaining its efficiency level, enabling the same motor size to produce more power.
DR motors will be available in three versions – a standard model and two high efficiency versions. The standard model is designed for high cycling applications like material handling and packaging, where frequent starts and stops would counteract any energy savings that could be gained from using a premium efficiency motor.
One energy efficient version meets the requirements of NEMA Premium for the U.S. market and the other complies with the efficiency requirements of other countries, including the new IEC motor standard that will take effect in Europe in 2011.
The new DR motor series also addresses industry requirements for small, compact and decentralized drive solutions for material handling and transportation systems. SEW’s modular approach to product design allows engineers to select exactly the right motor, drive and gear unit combination to maximize energy savings in every application.
In another engineering innovation, SEW engineers integrated an encoder into the fan rather than at the end of the motor to help achieve a compact footprint. This built-in encoder is fully integrated into the motor, reducing the cost and complexity of encoder engineering. The simple encoder design also makes it easy to retrofit.
Many tasks require only simple positioning and velocity detection. Since high-resolution encoders installed on the non-drive shaft end are often too complex for this task, SEW has developed several fully integrated and affordable encoders for the DR motor with a resolution between one and 24 pulses per revolution. For high-resolution applications, standard-mounted encoders have been equipped with a new, simpler connection. Input shaft assembly makes for easier encoder changes. Several encoder types including sin/cosine, HTL, TTL, RS485 and others are available.
The modularity of the DR motor series is also reflected in a new braking system, which for the first time allows three different brake sizes to be used with a single motor size. Since many applications don’t require full braking torque, this modular approach provides choices, which can equate to cost and weight reductions. The new brakes are quieter and, since they are mounted on a friction plate, can be easily removed for maintenance or resizing without disassembling the motor. Sensors make monitoring for wear or operation simpler. As an alternate to a “holding brake,” a backstop with high locking torque can also lock the rotation of the motor in one direction.