27
28
Appendix:
a. Mechanical Vibration Rating Table
ISO2372
45
Vibration intensity
Applicable to the following machine
Vibration velocity Vrms(mm/s)
Notes:
1) Grade I is small-size electric motor (less than 15kW electric motor); Grade
II is medium-size electric motor (15kW-75kW electric motor); Grade III is
large original electric motor (hard base) ; grade IV is large original electric
motor (plastic base).
2) A, B, C, D is the vibration rating. A is great, B is satisfactory, C is discontent
and D is not allowed. The measurement velocity RMS value shall be on the
orthogonal intersection direction of shell bearing.
b. the maximum allowable vibration for electric motor higher than 1
horsepower
NEMA MG1-12.05
3000~4000
25.4
1500~2999
38.1
1000~1499
50.8
63.6
Peak-peak displacement amplitude
Rotating speed
999
