Casing
Casing made from sea water resistant aluminium. Base frame manufactured from galvanised steel with integrated inlet cone. Integrated bird guard manufactured from powder coated, galvanised steel.
Motor
Voltage controllable external rotor motors, suspended vibration-free.
Impeller geometry
Radial impeller with backward curved blades manufactured from high-performance composite material, with highlyefficient, profiled 3-D blade geometry.
Output control
3 phase motors speed controllable via transformer, 2 speed via star-delta switching. Frequency converter controllable by using an all-pole sinusoidal filter. The single phase motors can be controlled by transformer / thyristor or can
be operated in 2 speeds via a two speed switch.
Motor protection
Integrated thermal contacts, up to size 311 with manual reset; from size 355 integrated thermal contacts with cables for connection to a motor protection switching device.