Three-phase low-speed induction motors of the series MAAV are intended for direct drives of axial-flow fans for cooling towers without gears, for the environment with the ambient temperature up to +40°C. Due to a direct low speed the noise and vibration levels are reduced, life of the parts of the set is longer, the assembly costs are reduced and the requirements for maintenance are lower in comparison with a high-speed motor with a gearbox. Removal of a gearbox with oil filling is also beneficial for environment protection.
The motors are designed for a possibility of the speed- changing ratio 1:2, enabling thus a more economical adjustment of the cooling power of a tower in different climatic conditions. The frame is robust, made of grey cast iron, with ribs on the surface. The motor is cooled by external air flowing round the motor, inside the motor there is an auxiliary ventilation circuit. The motor is mounted in a vertical position with the upward shaft extension and withstands axial and radial loads from the axial-flow fan being driven.
|Power output||40 kW ÷ 200 kW|
|Speed range||100 ÷ 300 rpm|
|Voltage||380 V ÷ 690 V|
|Frame||Grey cast-iron, flat design|
|Class of insulation||F, H (VPI)|
|Degree of protection||IP 54 and higher|
|Method of cooling||Surrounding air or self ventilated|
|Type of construction||Vertical arrangements|