Motor Cooling; Natural Convection; Fan Units - Bosch Rexroth MSK030B-0900-NN Project Planning Manual

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Operating conditions and application notes
9.12

Motor cooling

9.12.1

Natural convection

9.12.2

Fan units

Rexroth motors in standard design are self-cooling. The heat dissipation is
realized via natural radiation to the ambient air and by heat conduction to the
machine structure. The nominal data are achieved at ambient temperatures
of up to 40 °C. Sufficient heat radiation must be ensured by the installation
situation. Unhindered vertical convection has to be ensured by a sufficient
distance of 100 mm to adjacent components on the side surfaces.
Contamination of the motors reduces heat dissipation. Pay atten‐
tion to cleanliness!
Fan units are available for certain motor types. The performance data given
in the technical data are marked with the index "S" for "surface". Descriptions
of the technical data of the available fan units can be found at
"Fan units for MSK motors" on page
Cooling takes place via air streams which are guided over the surface of the
motor by air baffles. The fan is designed to use clean air from its surround‐
ings to cool the motor.
The use of the fan under the following conditions is expressly not suitable:
● Delivery of air which contains abrasive particles
● Delivery of air which has a strongly corroding effect, e.g., salt mist
● Delivery of air which contains a high dust load, e.g., extraction of saw
dust
● Conveying of flammable gases/particles
● Use of the fan units as safety-related components or for the assumption
of safety-relevant functions
In order for the required air volume to be converted by the fan unit, a mini‐
mum distance must be maintained between the fan grille and the machine for
the air to be sucked in or blown out. The distance results from the motor
structure.
1 2
① Machine
② Air outlet space
① Air suction area
Fig. 9-13: Fan units installation area, minimum distance
Consider the minimum distance of the air supply ③ when designing the ma‐
chine.
DOK-MOTOR*-MSK********-PR12-EN-P
Synchronous Servomotors MSK
180.
1 2
3
80mm
chapter 7.2
80 mm
3