The housing supporting frames are double chamber aluminum profiles with
corners made of plastic and double skinned (20mm) galvanized steel panels
insulated with non-inflammable, noise and temperature insulating fiberglass mats.
One side of the casing is open as standard.
The impellers are balanced dynamically together with the external rotor motors at two levels according to
quality level G2.5/G6.3 DIN ISO 21940-11.
Up to size 560:
Backward curved centrifugal impellers made of plastic with galvanized steel support plates.
From size 630:
High efficiency backward curved centrifugal impellers made of aluminum
Motor and motor protection:
All Rosenberg fans are equipped with direct driven external rotor motors. All our fans have motor protection
through thermal contacts in the motor windings as standard. The motors apply to protection class IP44/IP54.
The drive has due to an external rotor motor a space saving, compact and attractive design.
The motor is fitted within the impeller, which enables the best possible cooling. For this reason
a 100% variable speed control can be guaranteed. V-belts, additional tension bars and motor
mounting devices are not necessary. Only well-dimensions ball-bearings, fitted on both sides
and life time greased are used. Both ball-bearing seats are ground to high precision in one
work process to eliminate any vibrations.
External rotor motors have an extremely low starting current. The windings comply to isolation
class F. In addition the windings have a standard moisture impregnation.
Direction of rotation:
Direction of rotation is clockwise, viewed from the inlet side.
WARNING: Counter-clockwise operation will cause overload damage to the motor!