WEG has launched a range of high-efficiency motors for water and wastewater treatment applications, that comply with Wimes – the UK’s Water Industry Mechanical and Electrical Specifications. The IEC-frame W22 motors exceed the requirements of the new IE2 (high) and IE3 (premium) efficiency classes, well ahead of the next phase of the EuP (Energy-using Products) regulations which will start to make IE3 mandatory from 2015.

The motors (above), backed by a three-year warranty, cover ratings from 0.75–375kW in two-, four- and six-pole configurations (with lower outputs and higher polarities available on request). An aerodynamic frame design increases airflow, thus reducing operating temperatures and minimising heat build-up, vibration and noise. This leads to extended lifetimes with low maintenance.

The motors’ terminal boxes are located to optimise airflow and cooling. The mains terminal box can be on the top, left- or right-hand side of the motor. For frame sizes 225S/M to 355A/B, the box can be moved to the left- or right-hand side without dismantling the motor.

The motors have dual-voltage (110/230V) space heaters terminated inside a separate terminal box. They also include three PTC thermistors for over-temperature protection (Wimes prohibits retrofitting thermistors after manufacture), and have insulated endshields from frame size 280 upwards. Bearing relubrication nipples are incorporated on frame sizes 160 and above.

A proprietary insulation technology increases the dielectric resistance of the motor windings, allowing operation with variable frequency drives at voltages up to 575V, without modification.