Motors meet efficiency standards

Edited by the Engineeringtalk editorial team May 5, 2008

The WEG W22 design provides better airflow over the motor casing, keeping temperatures within the optimum operating range and improving reliability.

WEG Electric Motors has released the W22 range of three-phase induction motors that offer reduced lifetime costs, lower noise and vibration, better reliability with a longer working life and easier maintenance.

The motors are being introduced in three different stages covering different frame sizes and outputs, with the 225 - 355 model (up to 400kW) frame size demonstrated by WEG at Drives and Controls '08, the 132 - 200 size to be released in early 2009 and the 63 - 112 size to be released in mid- 2009.

Siegfried Kreutzfeld, Technical Director of WEG Motors, said: "With losses reduced by between 10% and 40% across the range, W22 industrial motors deliver efficiency improvements equal to or better than EU Eff1".

"These advances will enable the W22 motors to meet the latest requirements for high energy efficiency".

"Further development of the W22 motors will enable them to meet the Premium Efficiency Category for the USA, before 2010 and Australia's Maximum Efficiency Program Series (MEPS)".

To deliver these improvements at lower running and lifetime cost of ownership, WEG has undertaken extensive redesign of key parts of the motors.

The WEG design provides better airflow over the motor casing, keeping temperatures within the optimum operating range and improving reliability.

Additional aerodynamic improvements to the casing exterior have enhanced the airflow effectiveness and minimised any hot spots.

The terminal box and the central eyebolt seating have been moved to reduce flow obstruction.

The lower temperature further enhances the benefits of WEG's Wise system, which offer prolonged resistance to temperature degradation of the insulation.

The W22 industrial motor range has been designed for operation with advanced frequency inverters, and offers flexibility and increased energy efficiency while resisting voltage spikes and voltage rise times.

It is available as a package with WEG's CFW11 Optimal Flux Frequency inverter drives.

Noise levels due to the ventilating system have been substantially reduced, by between 3 and 8dB(A).

This brings the W22 noise levels to between 72 and 80dB, substantially lower than IEC recommendations.

The W22 industrial motors are constructed of WEG's own high-quality cast iron to ensure maximum durability under harsh conditions.

Redesign of the fan cover (cowling) has also ensured greater strength to resist everyday impacts and accidents.

In addition, the end cover has been redesigned for improved heat dissipation from the bearings, while being strengthened for increased resistance to deformation and better bolt protection.

The feet are now cast integrally with the motor casing, giving greater stiffness, better damping in high-vibration installations and ensuring flatness for easy mounting on the motor plinth.

The strengthened feet have been designed with integral lifting holes.

This has enabled the eyebolt seating to be removed from the casing, for more even cooling.

Standard environmental protection is IP55.

This is easily upgraded to IP65 with a WEG adaptation kit, comprising a replacement housing with new bearing seals, for improved dust and water ingress protection, enabling high-pressure water cleaning to be employed.