Vibration converter
Convert vibration velocity between mm/s and in/s, and see which ISO severity band the reading falls in.
That's about the same as a machine at the usual alarm point. That is satisfactory: acceptable for unrestricted long-term running.
What it means
How rough is that?
Severity bands follow ISO 10816 for medium machines. Large machines on flexible mounts are allowed considerably more.
Every unit
Your vibration in every unit
Learn
Three things worth knowing
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1 in/s = 25.4 mm/s
US charts are drawn in inches per second, where 0.28 in/s is the usual alarm point. That is 7.1 mm/s on an ISO chart: the same line, different units.
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Why velocity, not shaking
Fatigue damage follows how fast the metal moves, not how far. Velocity turned out to track bearing and gear wear better than anything else measurable.
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RMS is not peak
A sine wave peak is 1.414 times its RMS. Quoting a peak figure against an RMS limit makes a healthy machine look like it is failing.
Shortcuts
Popular vibration conversions
Background
About vibration measurement
Machine condition is judged on RMS velocity, usually in millimeters per second over the 10–1000 Hz band. Velocity is used rather than displacement or acceleration because it stays roughly flat across that range, so one number describes the whole machine.