With motor efficiency regulations in place, what can the market offer?
The European Commission's energy efficiency regulations with regard to the minimum energy performance standards (MEPS) of electric motors are by now reasonably well-known throughout industry.
With the IE2 standard having been introduced in June 2011 and motors for most applications being required to meet IE3 standards by January 1st, 2015 (for motors >=7.5 to 375 kW), it is fair to say that that the move towards higher-efficiency motors is well underway. Having said that, there are some changes to the regulations of which not everyone may be aware. The European Commission has initiated a significant tightening of the energy-efficiency directive for electrical devices, leaving more users of drive technology facing new challenges. The exceptions of the 2009/640/EC Directive will be changed substantially as early as autumn 2013. One aspect will be particularly important for most users: the new definition of the range of very high and very low ambient temperatures in which conventional motors may be used. Up until now, IE1 motors could be used in applications with ambient temperatures below -15°C or above 40°C. In the future, however, the exception only applies to extreme temperatures below -30°C or above 60°C. However, as has long been argued by motor manufacturers, the legislation could not be accused of rushing anyone into adopting newer technologies. In consequence, the technology is some distance ahead of the regulations, with an abundance of super- and super-premium efficiency motors already on the market for those with the foresight (and budget) to invest in them. Eriks, for instance, has launched the Fenner FM:3 range, a series of low-voltage cast iron motors certified for IE3 efficiency. The design includes as standard features that are optional on many competitor products. The FM:3 range comprises 80 to 315 frame sizes and all motors are fitted with thermistors terminated in the terminal box. 180 to 315 frame sizes also include re-grease-able bearings with button-type grease nipple and grease-through system. Spring lip seals are standard on both drive end and non-drive end, while the multi-mount design allows feet to be repositioned due to the stator and feet being fully machined prior to assembly. In addition, the motor is a symmetrical design, allowing the terminal box to be moved towards the fan cowl. Meanwhile, the generous terminal box itself offers two cable entries, making connection on site an easy job. In parallel with the development of the cast iron FM:3 motor range, a range of aluminium IE2 efficiency motors has been developed in the shapeof the Fenner FM:2 range of low-voltage electric motors. Through increased energy efficiency levels the Fenner FM:2 and FM:3 motor ranges deliver premium efficiency levels and lower TCO (Total Cost of Ownership) over the lifespan of the product. Regal, meanwhile, offers SyMAX IHP (integral horsepower), a permanent magnet AC motor range whose radial flux design delivers high torque, ultra-high efficiency and increased power density, compared to conventional induction motors. It is a sister product to the SyMAX FHP (fractional horsepower) motor range. SyMAX IHP meets IE4 efficiencies with 15% lower losses than the equivalent NEMA Premium motor. It is lighter than a typical induction motor and features a totally enclosed, fan-cooled (TEFC) construction with shielded bearings and shaft seal. Another feature is the patented Max Guard insulation system, which combines corona-resistant magnet wire and a low stress winding configuration to guarantee dependable motor life even in the most demanding applications. The motor's IP55-rated enclosure also makes it perfect for applications that require a high degree of protection against the entry of dust, water and other contaminants. The very high torque-to-inertia ratio ensures a higher dynamic response, resulting in consistent and repeatable machine performance. In fact, its output power is such that in many cases a direct drive configuration is possible, eliminating mechanical driveline components such as gears and belts. The rare earth magnets not only enhance power, but also allow for significant energy savings, making the SyMAX IHP motor well suited for commercial and industrial machinery, pumping and many other applications. Bauer Gear Motor, meanwhile, has launched what it claims is the world's first Ex-rated, IE4 Super Premium Efficiency motor. Its S Series is the latest development to Bauer's PMSM (permanent magnet synchronous motor) range. An IE4 rating is the highest energy efficiency that can currently be achieved within motor technology, making the S Series the world's most efficient motor for use in explosion-hazardous areas. The launch of the S Series means that applications that require motors to be specified and designed to meet ATEX classifications can now benefit from similar energy savings as found in other industrial areas. Currently most Ex-e (Increased Safety) rated variable speed three-phase induction motors on the market are generally available in standard efficiency class IE1. While the efficiency of these can be improved with the addition of frequency inverters, they still fall well short in comparison to the improved design of IE3. IE4 motors are now implemented in the IEC standard IEC 60034-30 Edition 2 draft, in addition to the newly included IE efficiency level classified for variable speed motors. The S Series offers both Ex e rating and potential energy savings of up to 40% compared to an IE2 inverter-driven squirrel cage motor. The S series is part of Bauer's PMSM motor range which has been proven to provide the best possible energy efficiency. The range of motors is available from 0.55kW to 15kW and are classified for Zones 1 and 21. Not only are they superior at converting electrical energy into mechanical power, they also offer the added benefit of maintaining constant speed independent of the load. This means that motor speed does not vary, despite overload variations, or cases of voltage drop, as long as the mains frequency is kept constant. PMSM synchronous motors offer considerably improved efficiency compared to induction motors even under partial load conditions; and extremely high efficiency under rated operating conditions. They also have considerably higher power density, which, for geared motors, yields higher system efficiency with minimal installation volume – and also reduced weight. Save energy online For those looking for a high-efficiency motor, ABB has launched an online tool that makes it easier than ever to select motors to meet different minimum energy performance standards (MEPS). The tool makes it easy to choose the optimum motor to meet MEPS requirements as they change or are introduced to new areas. The Optimizer can be found at www.abb.com/motors&generators or can be downloaded from the Apple store for iPad use. Motor users can select motors, compare running costs and get further documents about their motors. The first stage in motor selection presents the user with eight drop down selection menus. Categories are MEPS area (e.g. EU, United States), efficiency class (IE2, IE3 etc), frame material, motor range, voltage, frequency, speed and power output. Once the required characteristics are selected, the tool presents a list of suitable motors. For instance, selecting EU MEPS, IE3, dust ignition proof motors, 400 V, 50 Hz, all poles and all outputs, returns a list of 49 suitable motors and their characteristics. Any of the suggested motors can be easily saved with one click. The next stage is to compare these motors to discover the cost of running them. Motors can be compared by running cost, payback periods, lifecycle savings and reduction in greenhouse gas emission. The Optimizer will also, if possible, automatically suggest a higher-efficiency motor and highlight the additional savings that could be realised by upgrading. Test reports, drawings, data sheets and other documents can be accessed quickly and easily for the selected motors. Documents can be opened on screen, saved or exported as a zip file. "Selecting the optimum motor to meet a specific MEPS can be a complicated task. With the Optimizer we've developed a tool that not only makes the job easy, but also provides running cost information and easy access to all the necessary documentation," says Ian Allan, general manager for ABB motors and generators in the UK."