Enter the broadband rms vibration velocity measured on a non rotating part of the machine, usually the bearing housing, then pick the machine group and the support condition to see the condition zone from A to D and how much margin is left to the next boundary. The measurement band is roughly 10 to 1000 Hz. Readings and boundaries are entered in in/s by default, with mm/s available in the unit menu, and every result shows in/s first with mm/s in parentheses.
Machine groups split at a rating above 300 kW and a rating of 15 to 300 kW, and a foundation whose lowest natural frequency sits above the main exciting frequency counts as rigid support, otherwise flexible. The boundaries come from material describing the international standard for evaluating vibration on rotating machinery, but the only sources are equipment vendor material and a translation of it, so all three values can be edited and the result states whether table values or your own are in use. Figures current as of October 2026.
Only the zone letter is reported; which zones allow continued running and what action each calls for are not offered here because no authoritative source confirmed them. The source does not say whether the limits are inclusive either, so a reading at or above a boundary is treated as the higher zone. Environmental vibration limit checks and daily vibration exposure from hand held tools are not covered. The published table is natively in mm/s rms (Group 2 rigid: 1.4, 2.8 and 4.5 mm/s, about 0.055, 0.110 and 0.177 in/s), so the check runs in mm/s after converting at 1 in = 25.4 mm. Many US meters display in/s peak; for a single sine wave peak is about 1.414 times rms, so convert before entering. This calculator is for reference and does not replace design. Review by a qualified engineer is required.
Frequently Asked Questions
The table used here comes only from equipment vendor material and a translation of it, so the values may differ from the original standard. All three boundaries can be overwritten so you can apply an in-house or manufacturer limit instead.
A reading at or above a boundary is treated as the higher zone. The source does not state whether the limits are inclusive, so this is a rule chosen here; nudge the boundary value if your own procedure differs.
Only the zone letter is reported. Which zones allow continued operation and what action each calls for follow the original standard and your own procedures, and are not offered here because no authoritative source confirmed them.