Vibration Response; Mounting And Mounting Instructions; Natural Frequency For Mounting - Siemens SIMOTICS M-1PH1 Equipment Manual

Mechanical properties

3.11 Vibration response

3.11 Vibration response
3.11.1

Mounting and mounting instructions

To ensure smooth, vibration-free motor operation, you must mount the motor correctly and
precisely by observing the mounting instructions carefully. For more information, see Section
"Mounting the motor (Page 57)".
3.11.2

Natural frequency for mounting

The motor is a system that can vibrate at its natural frequency. This natural frequency lies
above the specified maximum speed.
When the motor is mounted onto a machine, a new system, which is subject to vibration, is
created with modified natural frequencies. These frequencies can lie within the motor speed
range.
This can result in undesirable vibration in the mechanical drive transmission.
Note
Avoiding natural frequencies during mounting
The motor must be carefully mounted on adequately stiff foundations or bedplates.
Additional elasticities of the foundations or bedplates can result in resonance effects at the
natural frequency and operating speed and therefore result in inadmissibly high vibration
values.
The magnitude of the natural frequency occurring when the motor is mounted depends on
the following factors:
• Mechanical transmission elements (gearboxes, belts, couplings, pinions, and so on)
• Stiffness of the machine onto which the motor is mounted
• Stiffness of the motor in the area around the foot or customer flange
• Motor weight
• Machine weight and the weight of the mechanical system in the vicinity of the motor
• Damping properties of the motor and driven machine
• Construction type, that is, IM B5, IM B3, IM V5, and IM V1
• Motor weight distribution, that is, length and shaft height
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Equipment Manual, 09/2021, A5E51077676A-AA
1PH1 main motors