Posted to News on 10th May 2010, 14:44
New range of energy-efficient IE2 geared motors
IEC 60034-30 requires new three-phase AC electric motors rated from 0.75kW upwards to meet efficiency level IE2 from June 2011. Lenze is ready now for the change with a range of L-force geared motors that meet the efficiency levels and are also available with many standard options. The L-force range covers helical, shaft-mounted helical, bevel, helical bevel and helical worm designs in power ratings up to 45kW. Modular options such as brakes, fans and encoders are offered. Many thousands of models with output torques from 2-14,000Nm are available and it is said to be easy to change from an IE1 to an IE2 motor.
The new efficiency level IE2 (which corresponds approximately to the old Eff 1 efficiency) represents an efficiency gain of 2-3 per cent over the lower level of IE1. These new Lenze motors have efficiencies in a band from 80-92 per cent. Costs are inevitably higher, as the motor construction requires more copper, but, on a 2.2kW geared motor, the extra cost for the IE2 specification represents typically an increase of less than 10 per cent. Furthermore, although the efficiency gain from changing to IE2 is small, the payback times are short; in the case of a 2.2kW geared motor, the gain is 2.3 per cent and the payback is around 5000 running hours.
To achieve compact dimensions and low costs, Lenze uses AC motors that are integrated into the gearbox casing. Output torques and speeds are offered at 50Hz, 60Hz for America, and 87Hz (a frequency that gives increased power and dynamics, with the possibility of purchase cost reductions). Changing to IE2 causes small changes in the electrical data (lower running currents and higher starting currents) and also the rated motor speed. In some cases dimensions may change, although Lenze has been successful in minimising the change, with only two powers requiring a step up in frame sizes. Data in the same format is available for both IE1 and IE2 motors so that comparisons and changeover are easy.
Options
L-force geared motors have standard options covering most requirements. These include a choice of brakes, fans, incremental and absolute encoders, handwheels, rain covers and integral inverters. Surface protection for outside use and for cold areas with condensation is also offered. Geared motor delivery times are typically 2-4 weeks and urgent requirements for fast deliveries can usually be met.
Lenze L-force geared motors give designers a choice between standard IE1 and high-efficiency IE2 geared motors. They can be combined with high-efficiency gearboxes so that a motor efficiency of 92 per cent can be matched to a gearbox with efficiency of 97 per cent, making an energy-efficient drive system. With gearboxes already matched to the performance of the motor, designers have a simple task to select the optimum geared motor.
Follow the link for more information about Lenze L-force geared motors.
