Motor sound/ noise at low frequency

[Shark96]

Why motors are noisy at low rpm and sound gets normal at higher rpm/ frequencies?

 

[spacebeer]

I supose because at low rpm the torque is near max values....
Wait for better answers and for people with more knowledge...i'm Mechanical

 

[HamburgerHelper]

The frequency of the magnetostriction of your motor was in the inaudible range at higher rpm or not near a mechanical resonant frequency?

 

[GroovyGuy]

Hi Sark,
Are these motors running under VFD control, or are they single-speed DOL?
GG

The pessimist sees difficulty in every opportunity. The optimist sees the opportunity in every difficulty.
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