Siemens SIMOTICS DP 1PC13, Руководство по эксплуатации

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Description
3.3 Installation
Smoke extraction motors
Operating Instructions, 03/2016, 5 610 80000 40 018
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3.3.3 Cooling and ventilation
The machines of this series are three-phase asynchronous machines with a closed primary
(internal) cooling circuit and an open secondary cooling circuit (surface cooling). The surface
cooling varies depending on the version.
3.3.3.1 Machines with a fan
Self-ventilation (standard): Cooling IC 411 in accordance with 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.
The motors have a metal fan.
3.3.3.2 Machines without a fan (optional)
Surface cooling by relative movement of cooling air: Type of cooling IC 418 in accordance with
EN / IEC 60034-6
Image 3-2 IC418
3.3.4 Bearings
In order to support the machine shaft and maintain its position in the non-moving part of the
machine, only 2 rolling-contact bearings are used. One roller bearing performs the function
of a location bearing that transfers axial and radial forces from the rotating machine shaft to
the non-moving part of the machine. The second roller bearing is implemented as floating
and support bearing in order to allow thermal expansion inside the machine and transfer
radial forces.
The nominal (calculated) useful life of the bearings according to ISO 281 is at least 20,000
hours with utilization of the permissible radial/axial forces. 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).
Roller bearings with permanent lubrication are maintenance-free.