Noise in vertical electrical motor

we have a big noise in the electrical motor which it drives the lube oil pump.
95 KW, 400 V - 50Hz
Running speed : 2980 CPM 
Bearing roller type: DE & NDE: 6314 /C3
unfortunately we are facing a problem in our software, in fact, we use the screenshot from analyser Oneprod MVP2-2C to analyse the noise.
BPFO = 3.08
BPFI = 4.92
FTF = 0.38
2BSF = 2.05
1. As showning in the attached spectrum, there is a high peak at 281 Hz. 
2. the carrier frequency at 413 Hz modulated by running speed doesn't much with BPFI or their harmonics.
3.The second spectrum has a peak  at 2500 Hz modulated by 100 Hz; it is RBF modulated by 2 x LF ?

any0 1000 Hz RBFtwf help will be appriciedeted


Photos (3)
Original Post

Sorry for my confusion about your two different posts. In your 2nd spectrum, it looks like rotor bar or stator slot frequency (or harmonic) with modulation sidebands at 100-Hz from 2x line frequency. I assume motor runs on 50-Hz power. Unless the amplitude has changed significantly (>2x), I would not be too concerned. This is a normal pattern.


As mentioned above, the motor runs at 50 Hz. but as you can see that the amplitude is high on these peaks.
What about the first spectrum; there is a peak at 413 Hz modulated by running speed and there is a high peak at 281 Hz, I can't identify the original of the high amp
For 153 Hz, I think it is BPFI.


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