Standard backward-curved motorised impellers must be installed with a radiussed inlet ring to obtain published performance (see our product section on backward -curved motorised impellers).The inlet ring must be sourced as an accessory, and the correct clearance from the impeller must be maintained in order to optimise air performance.

The reversed backward curved motorised impeller is pre-assembled to its inlet ring. The impeller is reverse-mounted on the external rotor motor, drawing air through an inlet ring attached to the motor back-plate. The ring then functions as both radiussed inlet and a mounting facility for the complete unit. The fan is then immediately ready for assembling into equipment and for connection to the electrical supply. Finger guards are available for all models.

6 sizes of impeller are available in diameters 180, 192, 220, 225, 250 and 280

Low cost speed control is possible by supply voltage variation, either by electronic (triac) method or by transformer.