Table of Contents
Advertisement
Description
3.3 Design
3.3.2.1
Machines with a fan
Self-ventilation (standard): Cooling method IC 411 according to EN / IEC 60034-6
Located at the ND end of the stator housing is an air intake cowl that guides the external air on
its way to the motor. The external air is drawn in through openings in the air intake cowl and
flows axially across the outer cooling ribs of the motor frame. The fan wheel for the external
flow of cooling air is attached to the machine shaft.
The fan wheels are bidirectional.
Check the cooling effect below rated speed in the case of frequent switching or braking – or if
the speed is controlled continually below the rated speed.
Forced ventilation (optional): Type of cooling IC 416 in accordance with EN / IEC 60034-6
Cooling that does not depend on the speed is achieved by means of a unit that is independent
of the motor operating state (forced ventilation). This unit is closed to the outside by a fan cover.
It has its own main drive with fan impeller which creates the cooling air flow required for cooling
the motor.
3.3.3
Bearings
To support the machine shaft and maintain its position in the non-moving part of the machine,
DE and NDE rolling bearings are used. One end performs the function of a locating bearing that
transfers axial and radial forces from the rotating machine shaft to the non-moving part of the
machine. The opposite end is implemented as a floating and support bearing to allow thermal
expansion inside the machine and transfer radial forces.
The nominal (theoretical) service life of the bearings according to ISO 281 is at least 20,000
hours when the permissible radial/axial forces are complied with, and the machine is operated
on 50 Hz line supplies. However, the achievable useful life of the bearings can be significantly
longer in the case of lower forces (e.g. operation with self-aligning couplings).
Rolling bearings with permanent lubrication are maintenance-free.
32
1MB..5/6 shaft height 71 ... 355
Operating Instructions, 11/2023, A5E52779956A
Advertisement
Table of Contents
