Modular system
April 1st 2008

SEW-Eurodrive may not necessarily have reinvented the principles of standard asynchronous motors, but it has summarised and optimised current developments to introduce a new modular system for the DR motor series One recent development is to save as much energy as possible.An option to save energy is to operate electric motors exclusively via frequency inverters in a controlled fashion. But even the electric motor itself can make a contribution to reduce energy consumption.

Europe has been addressing the topic of energy savings by issuing the EuP guideline. SEW-Eurodrive has recognised this trend very early on and the company was the first to introduce energy efficient motors based on die-cast copper technology five years ago.

Another trend seems to become apparent by requirements from the logistics industry.There are demands for small, compact and decentralised drive solutions for use in handling and transportation systems.

Recognising trends and drawing conclusions

We have summarised and evaluated these and other trends.The result is a concept that has been introduced with the new modular DR motor system and is setting the new standard in drive engineering.The DR motor already meets future demands for minimum efficiency ratings of asynchronous motors.

We will continue to offer the proven MOVIMOT as part of the DR series of motors.The new generation is fully compatible with all other units and can be used with current motors of the DT/DV series.

The highlights of the DR motor The DR motor system integrates all current requirements regarding efficiency worldwide (Standard, High, and Premium).The motors are available with optional rotors featuring a copper cage of the second generation.

A new modular brake design gives you the choice of two or three brake sizes for each motor. Brake motors with inverter control require less braking action and therefore smaller braking torques are required for energy efficient motors. It is also a lot simpler to install or remove brakes of the BE generation as of size 90 DR motors.These BE brakes are mounted on a friction plate and can be easily removed.

Many tasks require only simple positioning and velocity detection (e.g. synchronous encoders).The high-resolution encoders installed on the non-drive shaft end are often far too complex for this task. We have developed two new, fully integrated and very affordable encoders for the DR motor.They can be easily retrofitted.The encoder resolution is between one and about 100 pulses per revolution.We will introduce a rotation counter in the near future.The mounted encoders have been optimized as well.The standard encoders can now be mounted directly to the shaft and fan guard even for larger motors, 4- pole from 7.5kW to 55kW.The mounted encoders with sine/cosine signals have been equipped with a new, simpler connection. Input shaft assembly makes for easier connection of encoder cable and change of encoder.

The motor feet for motors 71 to 132 can be easily retrofitted.The mechanical brake function can now be monitored with a standard option.You can either monitor the operation or wear or operation and wear.A backstop with high locking torque can now lock the rotation of the motor in one direction instead of a brake.The C1 profile of the overhead trolley system can now be operated with 4-pole, 1.1 kW drives. Sensors for temperature detection of the motor winding make for high efficiency of the drive in inverter operation.