Motor vibration
Motor vibration
(OP)
How can differentiate between electrical and mechanical frequency component in a motor spectra?
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RE: Motor vibration
Back to your question though- you would have to give us a bit more info on the application. Diagnosis of motor electrical vibration can vary depending on what kind of motor we are talking about, eg: DC, induction motor, synchronous motor, etc.
RE: Motor vibration
RE: Motor vibration
RE: Motor vibration
You can contact me at arnespamlind@algonet.se. Remove spam to get the address right.
RE: Motor vibration
Mechanical frequenties will be more in the neighbourhood of the eigenfrequencies of the mechanical structure. Those can be calculate by a finite element program or in rough by hand.
RE: Motor vibration
RE: Motor vibration
jameswhanna@yahoo.com
RE: Motor vibration
1. With the motor off: obtain the frequency response function (Accerleration/Force),with accelerometer mounted on the shaft and impacting the motor housing. This should provide the structural (mechanical) frequencies of the motor.
2. You can also get the power spectrum (narrow band frequency data) when you turn the power on with a holding torque (Acceleration response over a selected frequency range). your frequency maximum domain should be selected larger that the power cycle, >120 Hz or > 400Hz. 1600Hz will show for example a 400Hz and its harmonics of 800Hz.
Here you might get more acceleration response data by turning the shaft every 45 degrees fro 0 to 360, and the response reflect inner mechanical characteristics of the coil/armature/magnetic field interaction. Electrical frequency should be that of the power cycle.
3. The third motor behaviour you would like to get would be with motor running (steady state speed), and that would give you the operational modal characteristics. Here, bearing frequency should show clearly.
By no means the task is easy and requires good repeatable data sampling of an isolated motor (to avoid external interaction with motor support).
I hope this can be help to you.
RE: Motor vibration
Anybody have good case histories on SCR faults/diagnosis?
RE: Motor vibration