Some of the trends that have been seen in drive engineering, and indeed in systems generally, revolve around energy efficiency, compact design and cost-engineered equipment that is easy and economic to configure, install and maintain. SEW Eurodrive has recently introduced its new DR series of motors to meet these demands.
The trend in drive engineering to save as much energy as possible has been evident for some time. One way of saving energy is to operate electric motors exclusively via frequency inverters in a controlled fashion. But the electric motor itself can make a significant contribution to reducing energy consumption. Laws have already been passed in North America, Australia and New Zealand that prescribe the use of energy efficient motors. South America and many Asian countries are moving in the same direction.
Europe has been addressing the topic of energy savings by issuing the Energy-using Products (EuP) guideline. SEW Eurodrive recognised this trend early on and introduced energy efficient motors based on die-cast copper technology five years ago.
Another trend seems to become apparent from requirements of the logistics industry. There is demand for small, compact and decentralised drive solutions for use in handling and transportation systems.
These two trends and the ever-present need for cost effectiveness have been the drivers in developing SEW's new modular DR motor system. The DR motor already meets future requirements for minimum efficiency ratings of asynchronous motors.
The DR motor system
The DR motor system incorporates all current requirements regarding efficiency worldwide (Standard, High and Premium). The motors are available with optional rotors featuring a second generation copper cage.
A new modular brake design gives users 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.
Many tasks require only simple positioning and velocity detection (eg, synchronous encoders). The high-resolution encoders installed on the non-drive shaft end are often far too complex for this task. SEW has developed two new, fully integrated and very affordable encoders for the DR motor that can be easily retrofitted. The encoder resolution is between one and about 100 pulses per revolution. The mounted encoders have been optimised as well. The standard encoders can now be mounted directly to the shaft and fan guard. The mounted encoders with sine/cosine signals have been equipped with a new, simpler connection.
As a part of this re-engineering, the company has optimised motor sizes and available options:
* Many drives are more compact, ie, they are narrower or shorter when compared with the DT/DV series.
* The cable connection for small motors has been simplified and connection space has been enhanced.
* The optional connection with cage tension springs instead of a terminal board makes wiring easier for customers.
* The mechanical brake function (operation and/or wear) can now be monitored with a standard option.
* A backstop with high locking torque is available to lock the rotation of the motor in one direction instead of a brake.
* Sensors for temperature detection of the motor winding make for high efficiency of the drive in inverter operation.
SEEEM (Standards for Energy Efficiency of Electric Motor Systems)
Industrial electric motor systems use 40% of electricity worldwide. Their quality varies, largely because testing procedures and performance standards are not harmonised. In a globalised market, effective promotion of energy efficient products requires alignment of energy performance standards internationally.
SEEEM aims to stimulate and accelerate this process of harmonisation in order to save energy and reduce greenhouse gas emissions.
The public launch of SEEEM took place at the EEDAL'06 meeting in London on 20 June 2006. Over 40 representatives from 18 countries exchanged views on the proposed harmonisation programme. Since then two SEEEM meetings have taken place: 9 April 2007 at the Motors Summit'07 in Zurich Switzerland and 13/14 June 2007 at EEMODS'07 in Beijing China.
Source: www.seeem.org
For more information contact Rene Rose, marketing manager, SEW Eurodrive, +27 (0)11 248 7000, [email protected]
| Tel: | +27 11 248 7000 |
| Fax: | +27 11 248 7289 |
| Email: | [email protected] |
| www: | www.sew-eurodrive.co.za |
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