Issues related to the vibration of measuring equipment

mm/s is the vibration velocity. Vibration can usually be described by vibration displacement (μm), vibration velocity (mm/s), and vibration acceleration (m/s2 or g). The relationship between the displacement and time in simple harmonic motion can generally be expressed using sine or cosine functions; for example, X = ASin(f*t + 0.5). Here, A refers to the amplitude of vibration, that is, the vibration displacement. If this function is differentiated, the vibration velocity function is obtained; if the velocity function is differentiated further, the relationship between vibration acceleration and time is obtained. The vibration velocity commonly used to determine the severity of vibration hazards is the geometric mean of the vibration velocity over a certain period of time. I’m not sure if I made myself clear. I know some people will say that you’re wrong; displacement has nothing to do with vibration. I understand that what they are referring to is shaft displacement, which does not fall within the category of simple harmonic motion. For the radial vibration of rotating equipment, it can be completely treated as harmonic vibration. For radial vibration, as you have discussed, it can actually be expressed in terms of vibration velocity, or vibration acceleration, or it can also be expressed using vibration displacement, that is, the amplitude. Generally, for low-frequency vibrations (such as the radial and axial vibrations of sliding bearings), displacement is used to represent them; physically, this mainly reflects the clearance ； For high-frequency vibrations (such as those caused by bearing wear), acceleration is generally used to represent them; physically, it reflects the energy of the vibration ； For vibrations at normal frequencies (roughly in the range of 10–1000 Hz), using speed as a measure is generally sufficient.